Novel reactive compound, charge transporting film, photoelectric conversion device, electrophotographic photoreceptor and method of producing the same, process cartridge, and image forming apparatus

ABSTRACT

Provided is a reactive compound represented by the following General Formula (I): 
     
       
         
         
             
             
         
       
     
     wherein in General Formula (I), F represents a charge transporting skeleton, D represents a group represented by the following General Formula (III), and m represents an integer of from 1 to 8: 
     
       
         
         
             
             
         
       
     
     wherein in General Formula (III), L1 represents a divalent linking group including one or more —C(═O)—O— groups.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of application Ser. No. 13/430,242filed Mar. 26, 2012 which is based on and claims priority under 35 USC119 from Japanese Patent Application Nos. 2011-181009 and 2011-181011both filed Aug. 22, 2011. The disclosure of the prior applications ishereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

The present invention relates to a novel reactive compound, a chargetransporting film, a photoelectric conversion device, anelectrophotographic photoreceptor and a method of producing the same, aprocess cartridge, and an image forming apparatus.

2. Related Art

A cured film having a charge transport property is used in variousfields such as in an electrophotographic photoreceptor, an organicelectroluminescence element, a memory device, and a photoelectricconversion device such as a wavelength conversion device.

For example, in an electrophotographic image forming apparatus, thesurface of an electrophotographic photoreceptor is charged with apredetermined polarity and potential by a charging device, and thesurface of the charged electrophotographic photoreceptor is selectivelyerased by image exposure, whereby an electrostatic latent image isformed. Thereafter, a developing device attaches a toner to theelectrostatic latent image so as to develop the latent image as a tonerimage, and the toner image is transferred to a recording medium by atransfer unit, whereby the toner image is discharged as a formed image.

In view of improving the strength of the electrophotographicphotoreceptor, a suggestion for providing a protective layer on thesurface of the electrophotographic photoreceptor has been offered.

SUMMARY

According to an aspect of the invention, there is provided a reactivecompound represented by the following General Formula (I):

wherein in General Formula (I), F represents a charge transportingskeleton, D represents a group represented by the following GeneralFormula (III), and m represents an integer of from 1 to 8:

wherein in General Formula (III), L1 represents a divalent linking groupincluding one or more —C(═O)—O— groups.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention will be described indetail based on the following figures, wherein:

FIG. 1 is a schematic partial cross-sectional view showing anelectrophotographic photoreceptor according to the exemplary embodiment;

FIG. 2 is a schematic partial cross-sectional view showing anelectrophotographic photoreceptor according to the exemplary embodiment;

FIG. 3 is a schematic partial cross-sectional view showing anelectrophotographic photoreceptor according to the exemplary embodiment;

FIG. 4 is an IR spectrum of a compound (I)-7;

FIG. 5 is an IR spectrum of a compound (I)-15;

FIG. 6 is an IR spectrum of a compound (I)-17;

FIG. 7 is an IR spectrum of a compound (I)-23;

FIG. 8 is an IR spectrum of a compound (I)-25;

FIG. 9 is an IR spectrum of a compound (I)-27;

FIG. 10 is an IR spectrum of a compound (I)-30;

FIG. 11 is an IR spectrum of a compound (I)-43;

FIG. 12 is an IR spectrum of a compound (I)-46;

FIG. 13 is an IR spectrum of a compound (I)-53;

FIG. 14 is a schematic configuration view showing an image formingapparatus according to the exemplary embodiment;

FIG. 15 is a schematic configuration view showing an image formingapparatus according to another exemplary embodiment;

FIGS. 16 A to 16 C are views showing image patterns used respectivelyfor an image evaluation;

FIG. 17 is an IR spectrum of a compound (I′)-15; and

FIG. 18 is an IR spectrum of a compound (I′)-43.

DETAILED DESCRIPTION

Hereinafter, the exemplary embodiments of the invention will bedescribed with appropriate reference to attached drawings.

[Reactive Compound]

A novel reactive compound according to the exemplary embodiment is areactive compound represented by the following General Formula (I).

In General Formula (I), F represents a charge transporting skeleton, andD represents a group represented by the following General Formula (III).m represents an integer of from 1 to 8.

General Formula (III), L1 represents a divalent linking group includingone or more —C(═O)—O— groups.

The reactive compound according to the exemplary embodiment includes astyrene skeleton as a chain-polymerizable group that has a structure inwhich a vinyl group (—CH═CH₂) directly binds to a benzene ring, andshows excellent compatibility with an aryl group which is a mainskeleton of a charge transport agent. In a cured film using thiscompound, the aggregation of a charge transport structure and structuresaround the chain-polymerizable group that is caused by film shrinkage orcuring is inhibited. Accordingly, it is considered that the fluctuationof mobility is inhibited even if the film is repeatedly used. Inaddition, in the reactive compound of the exemplary embodiment, thecharge transporting skeleton and the styrene skeleton is linked to eachother via a linking group including a —C(═O)—O— group. Therefore, it isconsidered that the strength of the cured film is further improved dueto the interaction between the ester group and a nitrogen atom of thecharge transporting skeleton or between the ester groups.

The reactive compound of the exemplary embodiment is desirably acompound represented by the following General Formula (II), in view ofan excellent charge transport property.

In General Formula (II), each of Ar¹ to Ar⁴ independently represents asubstituted or unsubstituted aryl group. Ar⁵ represents a substituted orunsubstituted aryl group or a substituted or unsubstituted arylenegroup. D has the same definition as that of D in General Formula (I).Each of c1 to c5 represents an integer of from 0 to 2, and the sum of c1to c5 is an integer of from 1 to 8. k is 0 or 1.

L1 in General Formula (III) is desirably a divalent linking group formedby combining —C(═O)—O— with —(CH₂)_(n)— (here, n is an integer of from 1to 10).

Specifically, the group represented by General Formula (III) isdesirably a group represented by the following General Formula (IV), andmore desirably a group represented by the following General Formula (V).

In General Formula (IV), p represents an integer of from 0 to 4.

In General Formula (V), p represents an integer of from 0 to 4.

m in General Formula (I) or the sum of c1 to c5 in General Formula (II)is desirably an integer of from 2 to 6, more desirably an integer offrom 3 to 6, and particularly desirably an integer of from 4 to 6.

Hereinafter, as a specific example to which the reactive compoundaccording to the exemplary embodiment is applied, an electrophotographicphotoreceptor will be described.

If the surface of an electrophotographic photoreceptor is made into acured film, mechanical strength of the photoreceptor against repeateduse is improved, but image quality itself and the stability of the imagequality against repeated use are insufficient. Though unclear, thereason is considered to be as follows. By curing, the intermoleculardistance and conformation of a chemical structure providing the chargetransport property is changed from the state before curing, or chemicalstructures around the chain-polymerizable group and the chemicalstructures providing the charge transport property aggregaterespectively, the state of the film before curing is changed. Inaddition, when a film that includes a binder resin in addition to acharge transport material having a chain-polymerizable functional groupis cured, the compatibility between the structure of the chargetransport material and the binder resin is reduced due to the curing,which is also considered as the reason.

In this respect, the compatibility between the mechanical strength andimage quality that aims to the extension of the life of theelectrophotographic photoreceptor is important.

The electrophotographic photoreceptor (hereinafter, simply referred toas a “photoreceptor” in some cases) according to the exemplaryembodiment includes at least a conductive substrate and a photosensitivelayer provided on the conductive substrate. The electrophotographicphotoreceptor also includes a layer (Oc) as an uppermost surface layerwhich includes a polymerized or cured film of a composition containingthe compound represented by General Formula (I), that is, a compound(referred to as a “charge transport material (A1)” appropriately) with acharge transport property that has a structure in which one or morecharge transporting skeletons are linked to one or more styreneskeletons not conjugated with the charge transporting skeleton in thesame molecule and includes a —C(═O)—O— group (that is, an ester group)in a linking group that links the charge transporting skeleton to thestyrene skeleton.

In this exemplary embodiment, an electrophotographic photoreceptor isprovided in which scratches do not easily leave even if thephotoreceptor is repeatedly used, and image quality deterioration andimage degradation rarely occur.

The reason causing the photoreceptor of the exemplary embodiment toexert effects is not clarified. However, the reason why the imagequality deterioration rarely occurs even if the photoreceptor isrepeatedly used is assumed to be as below. It is considered that in thephotoreceptor that has a polymerized or cured film as an uppermostsurface, film shrinkage or aggregation of the charge transport structureand the structure around the chain-polymerizable group is caused by thepolymerization or curing. Consequently, if the photoreceptor surfacereceives mechanical stress due to the repeated use, the film itself isabraded or the chemical structure in a molecule is broken. Accordingly,the film shrinkage or aggregation state is changed greatly, andelectrical characteristics of the photoreceptor are changed, which leadsto the image quality deterioration.

On the other hand, in the exemplary embodiment, a styrene skeleton isused as the chain-polymerizable group, and the styrene skeleton hasexcellent compatibility with an aryl group which is a main skeleton of acharge transport agent. Therefore, it is considered that the imagequality deterioration caused by the repeated use is inhibited since theaggregation of the charge transport structure and the structure aroundthe chain-polymerizable group caused by the film shrinkage or curing isinhibited.

Moreover, in the exemplary embodiment, the charge transporting skeletonis linked to the styrene skeleton via a linking group including a—C(═O)—O— group. Therefore, it is considered that the strength of thepolymerized or cured film is further improved due to the interactionbetween the ester group and a nitrogen atom in the charge transportingskeleton or between the ester groups.

The ester group included in the linking group may cause thedeterioration of the charge transport property or image qualitydeterioration in a highly humid condition, due to the polarity orhydrophilicity of the ester group. However, in the exemplary embodiment,a styrene skeleton more hydrophobic than (meth)acryl or the like is usedas a chain-polymerizable group, and accordingly, the deterioration ofcharge transport property or image quality deterioration such as imagedegradation is inhibited.

The photoreceptor according to the exemplary embodiment is notparticularly limited in terms of the layer configuration or the like, aslong as the photoreceptor has at least a conductive substrate and aphotosensitive layer provided on the conductive substrate and includes alayer (Oc) as an uppermost surface layer which includes a polymerized orcured film of a composition containing a charge transport material (A1)which is the reactive compound represented by General Formula (I).

The photosensitive layer according to the exemplary embodiment may be afunctional integration type of photosensitive layer having both a chargetransporting function and a charge generating function or a functionalseparation type of photosensitive layer that includes chargetransporting layer and a charge generating layer. Moreover, other layerssuch as an undercoat layer may also be provided.

If the surface of an electrophotographic photoreceptor is made into apolymerized or cured film, mechanical strength of the photoreceptoragainst repeated use is improved, but image quality itself and thestability of the image quality against repeated use are insufficient.Though unclear, the reason is considered to be as follows. By curing,the intermolecular distance and conformation of a chemical structureproviding the charge transport property is changed from the state beforecuring, or chemical structures around the chain-polymerizable group andthe chemical structures providing the charge transport propertyaggregate respectively, the state of the film before curing is changed.In addition, when a film that includes a binder resin in addition to acharge transport material having a chain-polymerizable functional groupis cured, the compatibility between the structure of the chargetransport material and the binder resin is reduced due to the curing,which is also considered as the reason.

In this respect, the compatibility between the mechanical strength andimage quality that aims to the extension of the life of theelectrophotographic photoreceptor is important.

The electrophotographic photoreceptor (hereinafter, simply referred toas a “photoreceptor” in some cases) according to the exemplaryembodiment includes at least a conductive substrate and a photosensitivelayer provided on the conductive substrate. The electrophotographicphotoreceptor also includes a layer (Oc) as an uppermost surface layerwhich includes a polymerized or cured film of a composition containingone or more kinds of charge transport materials (A2) that have astructure in which one or more charge transporting skeletons are linkedto one or more styrene skeletons not conjugated with the chargetransporting skeleton in the same molecule and includes one or moregroups selected from —C(═O)—, —N(R)—, —S—, or a group formed bycombining —C(═O)— with —O—, —N(R)—, or —S— in a linking group that linksthe charge transporting skeleton to the styrene skeleton.

In this exemplary embodiment, an electrophotographic photoreceptor isprovided in which scratches do not easily leave even if thephotoreceptor is repeatedly used, and image quality deterioration andimage degradation rarely occur.

The styrene skeleton included in the charge transport material (A2) ofthe exemplary embodiment refers to a structure in which a vinyl group(—CH═CH₂) directly binds to a benzene ring. The material may have asubstituent instead of a hydrogen atom of the benzene ring, and examplesof the substituent include an alkyl group, an alkoxy group, a halogenatom, and the like. However, the material desirably does not have asubstituent.

(Presumptive Reasons Producing Effects)

The reason causing the photoreceptor of the exemplary embodiment toexert the effects is not clear. However, the reason why the imagequality deterioration rarely occurs even if the photoreceptor isrepeatedly used is assumed to be as below. It is considered that in thephotoreceptor that has a polymerized or cured film as an uppermostsurface, film shrinkage or aggregation of the charge transport structureand the structure around the chain-polymerizable group is caused by thepolymerization or curing. Consequently, if the photoreceptor surfacereceives mechanical stress due to the repeated use, the film itself isabraded or the chemical structure in a molecule is broken. Accordingly,the film shrinkage or the aggregation state is changed greatly, andelectrical characteristics of the photoreceptor are changed, which leadsto the image quality deterioration. On the other hand, in the exemplaryembodiment, a styrene skeleton is used as the chain-polymerizable group,and the styrene skeleton has excellent compatibility with an aryl groupwhich is a main skeleton of a charge transport agent. Therefore, it isconsidered that the image quality deterioration caused by the repeateduse is inhibited since the aggregation of the charge transport structureand the structure around the chain-polymerizable group caused by thefilm shrinkage or curing is inhibited.

Moreover, in the exemplary embodiment, the charge transporting skeletonis linked to the styrene skeleton via a linking group having a specificgroup such as —C(═O)—, —N(R)—, or —S—. Therefore, it is considered thatthe strength of the polymerized or cured film is further improved due tothe interaction between the specific group and a nitrogen atom in thecharge transporting skeleton or between the specific groups.

The specific group such as —C(═O)—, —N(R)—, or —S— may cause thedeterioration of the charge transport property or image qualitydeterioration in a highly humid condition, due to the polarity orhydrophilicity of the group. However, in the exemplary embodiment, astyrene skeleton more hydrophobic than (meth)acryl or the like is usedas a chain-polymerizable group, and accordingly, the deterioration ofcharge transport property or image quality deterioration such as ghostis not found.

[Electrophotographic Photoreceptor]

Hereinafter, the configuration of the electrophotographic photoreceptorof the exemplary embodiment will be described.

The photoreceptor according to the exemplary embodiment is notparticularly limited in terms of the layer configuration or the like, aslong as the photoreceptor includes at least a conductive substrate and aphotosensitive layer provided on the conductive substrate, and has alayer (Oc) as an uppermost surface layer which includes a polymerized orcured film of a composition containing one or more kinds of chargetransport materials (A2) that have a structure in which one or morecharge transporting skeleton are linked to one or more styrene skeletonsin the same molecule and includes one or more groups selected from—C(═O)—, —N(R)—, —S—, or a group formed by combining —C(═O)— with —O—,—N(R)—, or —S— in a linking group that links the charge transportingskeleton to the styrene skeleton.

The photosensitive layer according to the exemplary embodiment may be afunctional integration type of photosensitive layer having both a chargetransporting function and a charge generating function or a functionalseparation type of photosensitive layer that includes a chargetransporting layer and a charge generating layer. Moreover, other layerssuch as an undercoat layer may also be provided.

Hereinafter, the configuration of the photoreceptor according to theexemplary embodiment will be described with reference to FIGS. 1 to 3,but the exemplary embodiment is not limited to FIGS. 1 to 3.

FIG. 1 is a schematic view showing an example of the layer configurationof the photoreceptor according to the exemplary embodiment. Thephotoreceptor shown in FIG. 1 has a layer configuration in which anundercoat layer 4, a charge generating layer 2A, a charge transportinglayer 2B-1, and a charge transporting layer 2B-2 are laminated on asubstrate 1 in this order, and a photosensitive layer is configured withthree layers including the charge generating layer 2A and the chargetransporting layers 2B-1 and 2B-2 (a first embodiment). In thephotoreceptor shown in FIG. 1, the charge transporting layer 2B-2corresponds the layer (Oc) of the exemplary embodiment that includes thereactive compound represented by General Formula (I). Hereinafter, thislayer of the exemplary embodiment in the first embodiment will bereferred to as a layer (Oc1) of the exemplary embodiment. The chargetransporting layer 2B-2 serves as the uppermost surface layer alsofunctions as a protective layer that protects the charge transportinglayer 2B-1.

FIG. 2 is a schematic view showing another example of the layerconfiguration in the photoreceptor according to the exemplaryembodiment. The photoreceptor shown in FIG. 2 has a layer configurationin which the undercoat layer 4, a charge generating layer 2A, and acharge transporting layer 2B are laminated on the substrate 1 in thisorder, and the photosensitive layer 2 is configured with two layersincluding the charge generating layer 2A and the charge transportinglayer 2B (a second embodiment). In the photoreceptor shown in FIG. 2,the charge transporting layer 2B corresponds to the layer (Oc) of theexemplary embodiment that includes the reactive compound represented byGeneral Formula (I). Hereinafter, this layer of the exemplary embodimentin the second embodiment will be referred to as a layer (Oc2) of theexemplary embodiment.

FIG. 3 is a schematic view showing the other example of the layerconfiguration in the photoreceptor according to the exemplaryembodiment. The photoreceptor shown in FIG. 3 has a layer configurationin which the undercoat layer 4 and a photosensitive layer 6 arelaminated on the substrate 1 in this order, and the photosensitive layer6 is a layer in which the functions of the charge generating layer 2Aand the charge transporting layer 2B shown in FIG. 2 are integrated (athird embodiment). In the photoreceptor shown in FIG. 3, the functionalintegration type of photosensitive layer 6 corresponds to the layer (Oc)of the exemplary embodiment that includes the reactive compoundrepresented by General Formula (I). Hereinafter, this layer of theexemplary embodiment in the third embodiment will be referred to as alayer (Oc3) of the exemplary embodiment.

Hereinafter, the first to third embodiments will be describedrespectively as examples of the photoreceptor according to the exemplaryembodiment.

—Conductive Substrate—

Any material may be used as the conductive substrate so long as thematerial has been used in the related art. Examples of the materialinclude paper, plastic film, or the like coated or impregnated with aconductivity-imparting agent, such as a plastic film provided with athin film (for example, metals such as aluminum, nickel, chromium, andstainless steel; and a film of aluminum, titanium, nickel, chromium,stainless steel, gold, vanadium, tin oxide, indium oxide, indium tinoxide (ITO), or the like). The shape of the substrate is not limited toa cylindrical shape, and the substrate may have an approximately sheetshape or plate shape.

The conductive substrate particles desirably have conductivity in whichvolume resistivity is less than 10⁷ Ω·cm, for example.

When a metal pipe is used as the conductive substrate, the surface ofthe pipe may remain as it is or may be treated in advance with mirrorsurface cutting, etching, anodization, rough cutting, centerlessgrinding, sand blasting, wet honing, or the like.

—Undercoat Layer—

The undercoat layer is provided optionally, for the purposes ofpreventing light reflection in the surface of the conductive substrate,preventing unnecessary inflow of a carrier to the photosensitive layerfrom the conductive substrate, and the like.

The undercoat layer is configured with, for example, a binder resin andoptionally other additives.

Examples of the binder resin included in the undercoat layer includeknown polymeric resin compounds such as an acetal resin includingpolyvinyl butyral, a polyvinyl alcohol resin, casein, a polyamide resin,a cellulose resin, gelatin, a polyurethane resin, a polyester resin, amethacrylic resin, an acrylic resin, a polyvinyl chloride resin, apolyvinyl acetate resin, a vinyl chloride-vinyl acetate-maleic anhydrideresin, a silicone resin, a silicone-alkyd resin, a phenol resin, aphenol-formaldehyde resin, a melamine resin, and a urethane resin, acharge transporting resin having a charge transporting group, aconductive resin such as polyaniline, and the like. Among these, a resininsoluble in a coating solvent of the upper layer is desirably used, andparticularly, a phenol resin, a phenol-formaldehyde resin, a melamineresin, a urethane resin, an epoxy resin, and the like are desirablyused.

The undercoat layer may contain a metal compound such as a siliconcompound, an organic zirconium compound, an organic titanium compound,an organic aluminum compound, or the like.

The proportion between the metal compound and the binder resin is notparticularly limited and may be set within a range in which desiredcharacteristics of the electrophotographic photoreceptor are obtained.

In order to adjust the surface roughness, resin particles may be addedto the undercoat layer. Examples of the resin particles include siliconeresin particles, crosslinked polymethyl methacrylate (PMMA) resinparticles, and the like. In addition, to adjust the surface roughness,the surface of the formed undercoat layer may be polished. As thepolishing method, buffing, sand blasting, wet honing, grinding, and thelike are used.

Herein, examples of the configuration of the undercoat layer include aconfiguration that contains at least a binder resin and conductiveparticles. The conductive particles desirably have conductivity in whichvolume resistivity is, for example, less than 10⁷ Ω·cm.

Examples of the conductive particles include metal particles (particlesof aluminum, copper, nickel, silver, or the like), conductive metallicoxide particles (particles of antimony oxide, indium oxide, tin oxide,zinc oxide, or the like), and conductive material particles (particlesof carbon fiber, carbon black, graphite powder, or the like). Amongthese, conductive metallic oxide particles are suitable. The conductiveparticles may be used a mixture of two or more kinds thereof.

The conductive particles may be surface-treated using a hydrophobicizingagent (for example, a coupling agent) to adjust resistance.

The content of the conductive particles in the undercoat layer is, forexample, desirably from 10% by weight to 80% by weight, and moredesirably from 40% by weight to 80% by weight, based on the binderresin.

For the formation of the undercoat layer, a coating liquid for formingan undercoat layer obtained by adding the above components to a solventis used.

As methods of dispersing the particles in the coating liquid for formingan undercoat layer, a media dispersing machine such as a ball mill, avibration ball mill, an attritor, a sand mill, or a horizontal sandmill; stirring; and a media-less dispersing machine such as anultrasonic dispersing machine, a roll mill, or a high pressurehomogenizer are used. Herein, examples of the high pressure homogenizerinclude a collision type which disperses a dispersion throughliquid-to-liquid collision or liquid-to-wall collision in a highpressure state, a penetration type which disperses the dispersion bycausing the dispersion to penetrate a fine flow path in a high pressurestate, and the like.

Examples of a method coating the coating liquid for forming an undercoatlayer onto the conductive substrate include dip coating, push-upcoating, wire bar coating, spray coating, blade coating, knife coating,curtain coating, and the like.

The film thickness of the undercoat layer is desirably 15 μm or more,and more desirably from 20 μm to 50 μm.

Though not shown in the drawing, an interlayer may be provided betweenthe undercoat layer and the photosensitive layer.

Examples of the binder resin used for the interlayer include polymericresin compounds such as an acetal resin including polyvinyl butyral, apolyvinyl alcohol resin, casein, a polyamide resin, a cellulose resin,gelatin, a polyurethane resin, a polyester resin, a methacrylic resin,an acrylic resin, a polyvinyl chloride resin, a polyvinyl acetate resin,a vinyl chloride-vinyl acetate-maleic anhydride resin, a silicone resin,a silicone-alkyd resin, a phenol-formaldehyde resin, a melamine resin,and organic metal compounds containing zirconium, titanium, aluminum,manganese, silicon atoms, and the like. These compounds may be usedalone, or may be used as a mixture of plural compounds or as apolycondensate. Among these, an organic metal compound containingzirconium or silicon is suitable in respect that residual potential islow, and potential change caused by environments and repeated use issmall in this compound.

For the formation of the interlayer, a coating liquid for forming aninterlayer obtained by adding the above components to a solvent is used.As a coating method for forming the interlayer, general methods such asdip coating, push-up coating, wire bar coating, spray coating, bladecoating, knife coating, and curtain coating are used.

The interlayer not only plays a role of improving a coating property ofthe upper layer, but also plays a role of an electrical blocking layer.However, when the film thickness of the interlayer is too large, anelectrical barrier becomes too strong, which leads to desensitization orpotential increase caused by repeated use in some cases. Accordingly,when the interlayer is formed, the film thickness thereof is desirablyset in a range of from 0.1 μm to 3 μm. In addition, the interlayer inthis case may be used as an undercoat layer.

—Charge Generating Layer—

The charge generating layer is configured with, for example, a chargegenerating material and a binder resin. Examples of the chargegenerating material include phthalocyanine pigments such as metal-freephthalocyanine, chlorogallium phthalocyanine, hydroxygalliumphthalocyanine, dichlorotin phthalocyanine, and titanyl phthalocyanine.The examples particularly include chlorogallium phthalocyanine crystalshaving strong diffraction peaks at Bragg angles (2θ±0.2°) of at least7.4°, 16.6°, 25.5°, and 28.3° with respect to an X-ray with CuKαcharacteristics, metal-free phthalocyanine crystals having strongdiffraction peaks at Bragg angles (2θ±0.2°) of at least 7.7°, 9.3°,16.9°, 17.5°, 22.4°, and 28.8° with respect to an X-ray with CuKαcharacteristics, hydroxygallium phthalocyanine crystals having strongdiffraction peaks at Bragg angles (2θ±0.2°) of at least 7.5°, 9.9°,12.5°, 16.3°, 18.6°, 25.1°, and 28.3° with respect to an X-ray with CuKαcharacteristics, and titanyl phthalocyanine crystals having strongdiffraction peaks at Bragg angles (2θ±0.2°) of at least 9.6°, 24.1°, and27.2° with respect to an X-ray with CuKα characteristics. Examples ofthe charge generating material also include a quinone pigment, aperylene pigment, an indigo pigment, a bisbenzimidazole pigment, ananthrone pigment, a quinacridone pigment, and the like. These chargegenerating materials may be used alone or used as a mixture of two ormore kinds thereof.

Examples of the binder resin configuring the charge generating layerinclude a bisphenol A type or bisphenol Z type polycarbonate resin, anacrylic resin, a methacrylic resin, a polyarylate resin, a polyesterresin, a polyvinyl chloride resin, a polystyrene resin, anacrylonitrile-styrene copolymer resin, an acrylonitrile-butadienecopolymer, a polyvinyl acetate resin, a polyvinyl formal resin, apolysulfone resin, a styrene-butadiene copolymer resin, a vinylidenechloride-acrylonitrile copolymer resin, a vinyl chloride-vinylacetate-maleic anhydride resin, silicone resin, a phenol-formaldehyderesin, a polyacrylamide resin, a polyamide resin, apoly-N-vinylcarbazole resin, and the like. These binder resins may beused alone or used as a mixture of two or more kinds thereof.

The mixing ratio between the charge generating material and the binderresin is desirably in a range of from 10:1 to 1:10, for example.

For the formation of the charge generating layer, a coating liquid forforming a charge generating layer obtained by adding the abovecomponents in a solvent is used.

As a method of dispersing particles (for example, the charge generatingmaterial) in the coating liquid for forming a charge generating layer, amedia dispersing machine such as a ball mill, a vibration ball mill, anattritor, a sand mill, or a horizontal sand mill; stirring; and amedia-less dispersing machine such as an ultrasonic dispersing machine,a roll mill, or a high pressure homogenizer are used. Herein, examplesof the high pressure homogenizer include a collision type whichdisperses a dispersion through liquid-to-liquid collision orliquid-to-wall collision in a high pressure state, a penetration typewhich disperses the dispersion by causing the dispersion to penetrate afine flow path in a high pressure state, and the like.

Examples of a method coating the coating liquid for forming a chargegenerating layer onto the undercoat layer include dip coating, push-upcoating, wire bar coating, spray coating, blade coating, knife coating,curtain coating, and the like.

The film thickness of the charge generating layer is set desirably in arange of from 0.01 μm to 5 μm, and more desirably in a range of from0.05 μm to 2.0 μm.

—Charge Transporting Layer 2B-1 (Case of the First Embodiment)—

The charge transporting layer 2B-1 corresponds to the case of the firstembodiment, and is configured with a charge transport material andoptionally a binder resin.

Examples of the charge transport material include an oxadiazolederivative such as 2,5-bis(p-diethylaminophenyl)-1,3,4-oxadiazole; apyrazoline derivative such as 1,3,5-triphenyl-pyrazoline or1-[pyridyl-(2)]-3-(p-diethylaminostyryl)-5-(p-diethylaminostyryl)pyrazoline;an aromatic tertiary amino compound such as triphenylamine,N,N′-bis(3,4-dimethylphenyl)biphenyl-4-amine,tri(p-methylphenyl)aminyl-4-amine, or dibenzylaniline; an aromatictertiary diamino compound such asN,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine; a 1,2,4-triazinederivative such as3-(4′-dimethylaminophenyl)-5,6-di-(4′-methoxyphenyl)-1,2,4-triazine; ahydrazone derivative such as4-dimethylaminobenzaldehyde-1,1-diphenylhydrazone; a quinazolinederivative such as 2-phenyl-4-styryl-quinazoline; a benzofuranderivative such as 6-hydroxy-2,3-di(p-methoxyphenyl)benzofuran; anα-stilbene derivative such as p-(2,2-diphenylvinyl)-N,N-diphenylaniline; an enamine derivative; a carbazole derivative such asN-ethylcarbazole; hole transport materials such as poly-N-vinylcarbazoleand a derivative thereof; a quinone-based compound such as chloranil orbromoanthraquinone; a tetracyanoquinodimethane-based compound; afluorenone compound such as 2,4,7-trinitrofluorenone or2,4,5,7-tetranitro-9-fluorenone; a xanthone-based compound; and anelectron transport material such as a thiophene compound; and a polymerhaving a group including the above compounds in a main chain or a sidechain thereof. These charge transport materials may be used alone or incombination of two or more kinds thereof.

Examples of the binder resin configuring the charge transporting layer2B-1 include bisphenol A type or bisphenol Z type polycarbonate resin,an acrylic resin, a methacrylic resin, a polyarylate resin, a polyesterresin, a polyvinyl chloride resin, a polystyrene resin, anacrylonitrile-styrene copolymer resin, an acrylonitrile-butadienecopolymer resin, a polyvinyl acetate resin, a polyvinyl formal resin, apolysulfone resin, a styrene-butadiene copolymer resin, a vinylidenechloride-acrylonitrile copolymer resin, a vinyl chloride-vinylacetate-maleic anhydride resin, a silicone resin, a phenol-formaldehyderesin, a polyacrylamide resin, a polyamide resin, an insulating resinsuch as chlorinated rubber, an organic photoconductive polymer such aspolyvinyl carbazole, polyvinyl anthracene, or polyvinyl pyrene, and thelike. These binder resins may be used alone or used as a mixture of twoor more kinds thereof.

The mixing ratio between the charge transport material and the binderresin is desirably from 10:1 to 1:5, for example.

The charge transporting layer 2B-1 is formed using a coating liquid forforming the charge transporting layer 2B-1 obtained by adding the abovecomponents to a solvent.

As a method of coating the coating liquid for forming the chargetransporting layer 2B-1 onto the charge generating layer, a generalmethod such as dip coating, push-up coating, wire bar coating, spraycoating, blade coating, knife coating, or curtain coating is used.

The film thickness of the charge transporting layer 2B-1 is setdesirably to a range of from 5 μm to 50 μm, and more desirably to arange of from 10 μm to 40 μm.

—Charge Transporting Layer 2B-2 (Corresponding to Layer (Oc1) of theExemplary Embodiment in the First Embodiment)—

The layer (Oc1) of the exemplary embodiment is a layer

which includes a polymerized or cured film of a composition containingone or more kinds of the charge transport materials (A1) that have astructure in which one or more charge transporting skeletons are linkedto one or more styrene skeletons in the same molecule and includes oneor more —C(═O)—O— groups in a linking group that links the chargetransporting skeleton to the styrene skeleton, or containing one or morekinds of the charge transport materials (A2) that include one or moregroups selected from —C(═O)—, —N(R)—, —S—, or a group formed bycombining —C(═O)— with —O—, —N(R)—, or —S—.

The styrene skeleton included in the charge transport materials (A1) and(A2) in the exemplary embodiment is a structure in which a vinyl group(—CH═CH₂) directly binds to a benzene ring, but the material may have asubstituent instead of the hydrogen atom of the benzene ring. Examplesof the substituent include an alkyl group, an alkoxy group, a halogenatom, and the like. However, the material more desirably does not have asubstituent.

Hereinafter, the composition for forming the charge transporting layer2B-2 will be described.

As the charge transporting skeleton in the charge transport material(A1) of the exemplary embodiment, the skeleton described for the chargetransporting layer 2B-1 is exemplified. As the charge transportingskeleton, those including an arylamine skeleton are desirable, and amongthese, those including an triarylamine skeleton are more desirable.

Hereinafter, more desirable structure of the charge transport material(A1) of the exemplary embodiment will be shown as General Formula (II).

In General Formula (II), each of Ar¹ to Ar⁴ independently represents asubstituted or unsubstituted aryl group; Ar⁵ represents a substituted orunsubstituted aryl group or a substituted or unsubstituted arylenegroup; and D represents a group represented by General Formula (III). InGeneral Formula (III), L1 represents a divalent linking group includingone or more —C(═O)—O— group.

Each of c1 to c5 in General Formula (II) represents an integer of from 0to 2 and may be the same as or different from each other. Here, the sumof c1 to c5 in General Formula (II) is an integer of from 1 to 8. k is 0or 1.

The total number of styrene skeletons in General Formula (I) correspondsto m. The total number of styrene skeletons in General Formula (II)corresponds to a value of c1+c2+k×(c3+c4)+c5.

The lower limit of the total number of styrene skeletons in GeneralFormulae (I) and (II) is desirably 2 or greater, more desirably 3 orgreater, and even more desirably 4 or greater, in view of obtaining astronger crosslinked film (cured film). If the number of thechain-polymerizable group in a molecule is too large, as thepolymerization (crosslinking) reaction proceeds, it becomes moredifficult for molecules to move. Consequently, chain-polymerizationreactivity is reduced, and the proportion of unreactedchain-polymerizable groups increases. Therefore, the upper limit of thenumber of the styrene skeletons in General Formula (II) is desirably 7or less, and more desirably 6 or less.

D in General Formula (II) is a group represented by General Formula(III), and L1 represents a divalent linking group including one or more—C(═O)—O— groups.

L1 in General Formula (III) represented by D in General Formula (II) isnot particularly limited as long as L1 is a divalent linking groupincluding the ester group. Specific examples of L1 include divalentgroups formed by arbitrarily combining the ester group with a residue ofsaturated hydrocarbon (including all of linear, branched, and cyclichydrocarbons) or aromatic hydrocarbon as well as an oxygen atom. L1 isdesirably formed by arbitrarily combining the ester group with a residueof linear saturated hydrocarbon.

The total number of carbon atoms included in L1 in General Formula (II)is desirably from 1 to 20, and more desirably from 2 to 10, in view ofthe density and chain polymerization reactivity of the styrene skeletonsin a molecule.

In General Formula (II), each of Ar¹ to Ar⁴ independently represents asubstituted or unsubstituted aryl group. Each of Ar¹ to Ar⁴ may be thesame as or different from each other. Herein, examples of thesubstituent in the substituted aryl group include an alkyl group havingfrom 1 to 4 carbon atoms, an alkoxy group having from 1 to 4 carbonatoms, a phenyl group substituted with an alkoxy group having from 1 to4 carbon atoms, an unsubstituted phenyl group, an aralkyl group havingfrom 7 to 10 carbon atoms, and a halogen atom, other than D.

Ar¹ to Ar⁴ are desirably any one of the following Structural Formulae(1) to (7). The following Structural Formulae (1) to (7) in commonexhibit “-(D)c” that may be linked to each of Ar¹ to Ar⁴. Herein,“-(D)c” has the same definition as “-(D)c1 to -(D)c4” in General Formula(II), and desirable examples thereof are also the same.

In the Structural Formula (1), R⁰¹ represents one kind selected from agroup consisting of a hydrogen atom, an alkyl group having from 1 to 4carbon atoms, a phenyl group substituted with an alkyl group having from1 to 4 carbon atoms or an alkoxy group having from 1 to 4 carbon atoms,an unsubstituted phenyl group, and an aralkyl group having from 7 to 10carbon atoms.

In the Structural Formulae (2) and (3), each of R⁰² to R⁰⁴ independentlyrepresents one kind selected from a group consisting of a hydrogen atom,an alkyl group having from 1 to 4 carbon atoms, an alkoxy group havingfrom 1 to 4 carbon atoms, a phenyl group substituted with an alkoxygroup having from 1 to 4 carbon atoms, an unsubstituted phenyl group, anaralkyl group having from 7 to 10 carbon atoms, and a halogen atom. mrepresents an integer of from 1 to 3.

In the Structural Formula (7), Ar represents a substituted orunsubstituted arylene group.

Herein, Ar in Formula (7) is desirably represented by the followingStructural Formula (8) or (9).

In the Structural Formulae (8) and (9), each of R⁰⁵ and R⁰⁶independently represents one kind selected from a group consisting of ahydrogen atom, an alkyl group having from 1 to 4 carbon atoms, an alkoxygroup having from 1 to 4 carbon atoms, a phenyl group substituted withan alkoxy group having from 1 to 4 carbon atoms, an unsubstituted phenylgroup, an aralkyl group having from 7 to 10 carbon atoms, and a halogenatom. Each q represents an integer of from 1 to 3.

In the Structural Formula (7), Z′ represents a divalent organic linkinggroup. Z′ is desirably represented by any one of the followingStructural Formulae (10) to (17). p represents 0 or 1.

In the Structural Formulae (10) to (17), each of R⁰⁷ and R⁰⁸independently represents one kind selected from a group consisting of ahydrogen atom, an alkyl group having from 1 to 4 carbon atoms, a phenylgroup substituted with an alkyl group having from 1 to 4 carbon atoms oran alkoxy group having from 1 to 4 carbon atoms, an unsubstituted phenylgroup, an aralkyl group having from 7 to 10 carbon atoms, and a halogenatom; W represents a divalent group; each of r and s independentlyrepresents an integer of from 1 to 10; and each t represents an integerof from 1 to 3.

W in the Structural Formulae (16) and (17) is desirably any one ofdivalent groups represented by the following (18) to (26). Here, inFormula (25), u represents an integer of from 0 to 3.

In General Formula (II), when k is 0, Ar⁵ is a substituted orunsubstituted aryl group, and examples of the aryl group include thesame aryl group as exemplified in the description for Ar¹ to Ar⁴. When kis 1, Ar⁵ is a substituted or unsubstituted arylene group, and examplesof the arylene group include an arylene group obtained by removing onehydrogen atom in a desired position from the aryl group exemplified inthe description for Ar¹ to Ar⁴.

The composition for forming the charge transporting layer 2B-2 mayfurther contain at least one or more kinds of the charge transportmaterial (A2) of the exemplary embodiment. The charge transport material(A2) of the exemplary embodiment is not particularly limited as long asthis material is a compound that has a structure in which one or morecharge transporting skeletons are linked to one or more styreneskeletons in the same molecule and includes one or more groups selectedfrom —C(═O)—, —N(R)—, —S—, or a group formed by combining —C(═O)— with—O—, —N(R)—, or —S— in a linking group that links the chargetransporting skeleton to the styrene skeleton. Herein, R represents ahydrogen atom, an alkyl group, an aryl group, or an aralkyl group. Asthe charge transporting skeleton in the charge transport material (A2)of the exemplary embodiment, those described for the charge transportinglayer 2B-1 are exemplified. As the charge transporting skeleton, thoseincluding an arylamine skeleton are desirable, and among these, thoseincluding a triarylamine skeleton are more desirable.

Hereinafter, a more desirable structure of the charge transport material(A2) of the exemplary embodiment will be shown as General Formula (II′)

In General Formula (II′), each of Ar¹ to Ar⁴ independently represents asubstituted or unsubstituted aryl group; Ar⁵ represents a substituted orunsubstituted aryl group or a substituted or unsubstituted arylenegroup; and D is a group represented by General Formula (III′).

In General Formula (III′), L2 represents a divalent linking groupincluding one or more groups selected from —C(═O)—, —N(R)—, —S—, or agroup formed by combining —C(═O)— with —O—, —N(R)—, or —S—. R representsa hydrogen atom, an alkyl group, an aryl group, or an aralkyl group.

Each of c1 to c5 in General Formula (II′) represents an integer of from0 to 2, and may be the same as or different from each other. Here, thesum of c1 to c5 in General Formula (II′) is an integer of from 1 to 8. kis 0 or 1.

The total number of styrene skeletons in General Formula (I′)corresponds to m. The total number of styrene skeletons in GeneralFormula (II′) corresponds to a value of c1+c2+k×(c3+c4)+c5.

The lower limit of the total number of styrene skeletons in GeneralFormulae (I′) and (II′) is desirably 2 or greater, and more desirably 4or greater, in view of obtaining a stronger crosslinked film (curedfilm). Generally, if the number of the chain-polymerizable group in amolecule is too large, as the polymerization (crosslinking) reactionproceeds, it becomes more difficult for molecules to move. Consequently,chain-polymerization reactivity is reduced, and the proportion ofunreacted chain-polymerizable groups increases. Therefore, the upperlimit of the total number of the styrene skeletons in General Formula(I′) is desirably 7 or less, and more desirably 6 or less.

D in General Formula (II′) is a group represented by General Formula(III′). L2 is a divalent linking group including one or more groups(hereinafter, referred to as a specific group (Lx)) selected from—C(═O)—, —N(R)—, —S—, or a group formed by combining —C(C═O)— with —O—,—N(R)—, or —S—. Herein, R represents a hydrogen atom, an alkyl group, anaryl group, or an aralkyl group.

The specific group (Lx) is desirably —C(═O)—, —N(R)—, —S—, —C(═O)—O—,—C(═O)—N(R)—, —C(═O)—S—, —O—C—(═O)—O—, or —O—C—(═O)—N(R)—, moredesirably —N(R)—, —S—, —C(═O)—O—, or —C(═O)—N(H)—, and most desirably—C(═O)—O—.

L2 in General Formula (III′) is not particularly limited as long as L2includes the specific group (Lx). Specific examples of L2 includedivalent groups formed by arbitrarily combining the specific group (Lx)with a residue of saturated hydrocarbon (including all of linear,branched, and cyclic hydrocarbons) or aromatic hydrocarbon, and anoxygen atom. L2 is desirably formed by arbitrarily combining thespecific group (Lx) with a residue of linear saturated hydrocarbon andan oxygen atom.

The total number of carbon atoms included in L2 in General Formula(III′) is desirably from 1 to 20, and more desirably from 2 to 10, inview of the density and chain polymerization reactivity of the styreneskeletons in a molecule.

In General Formula (II′), each of Ar¹ to Ar⁴ independently represents asubstituted or unsubstituted aryl group. Each of Ar¹ to Ar⁴ may be thesame as or different from each other. Herein, examples of thesubstituent in the substituted aryl group include an alkyl group havingfrom 1 to 4 carbon atoms, an alkoxy group having from 1 to 4 carbonatoms, a phenyl group substituted with an alkoxy group having from 1 to4 carbon atoms, an unsubstituted phenyl group, an aralkyl group havingfrom 7 to 10 carbon atoms, and a halogen atom, other than D.

Ar¹ to Ar⁴ are desirably any one of the above Structural Formulae (1) to(7). The Structural Formulae (1) to (7) in common exhibit “-(D)c” thatmay be linked to each of Ar¹ to Ar⁴. Herein, “-(D)c” has the samedefinition as “-(D)c1 to -(D)c4” in General Formula (II′), and desirableexamples thereof are also the same.

Hereinafter, specific examples of the compounds represented by GeneralFormulae (I) and (I′) will be shown. However, the compounds representedby General Formulae (I) and (I′) are not limited to the examples.

First, as specific examples of a charge transporting skeleton F in acase where the total number of D in General Formulae (I) and (I′) is 1,“(1)-1” to “(1)-25” will be shown. However, the exemplary embodiment isnot limited to the examples. In addition, a portion in each structuralformula shows that this portion is linked to D in General Formulae (I)and (I′).

Next, as specific examples of the charge transporting skeleton F in acase where the total number of D in General Formulae (I) and (I′) is 2,“(2)-1” to “(2)-29” will be shown. However, the exemplary embodiment isnot limited to the examples. In addition, a portion * in each structuralformula shows that this portion is linked to D in General Formulae (I)and (I′).

Next, as specific examples of the charge transporting skeleton F in acase where the total number of D in General Formulae (I) and (I′) is 3,“(3)-1” to “(3)-29” will be shown. However, the exemplary embodiment isnot limited to the examples. In addition, a portion * in each structuralformula shows that this portion is linked to D in General Formulae (I)and (I′).

Next, as specific examples of the charge transporting skeleton F in acase where the total number of D in General Formulae (I) and (I′) is 4,“(4)-1” to “(4)-31” will be shown. However, the exemplary embodiment isnot limited to the examples. In addition, a portion * in each structuralformula shows that this portion is linked to D in General Formulae (I)and (I′).

Next, as specific examples of D in General Formula (I) or (II), that is,specific examples the group represented by Formula (III), “(III)-1 to(III)-11” will be shown. A portion * in each structural formula showsthat this portion is linked to the charge transporting skeleton F inGeneral Formula (I) or to Ar¹ to Ar⁵ in General Formula (II).

Next, as specific examples of D in General Formula (I) or (II′), thatis, specific examples of the group represented by Formula (III′),“(III′)-1 to (III′)-66” will be shown. A portion * in each structuralformula shows that this portion is linked to the charge transportingskeleton F in General Formula (I′) or to Ar¹ to Ar⁵ in General Formula(II′).

Next, as specific examples of the reactive compound represented byGeneral Formula (I), “(I)-1” to “(I)-60” will be shown below, but theexemplary embodiment is not limited to the examples. In addition, theCTM skeleton structure in the following tables corresponds to the chargetransporting skeleton F in General Formula (I).

TABLE 1 CTM skeleton General Formula Compound structure (III) structure(I)-1 (1)-1 (III)-1 (I)-2 (1)-1 (III)-2 (I)-3 (1)-1 (III)-4 (I)-4 (1)-2(III)-5 (I)-5 (1)-2 (III)-7 (I)-6 (1)-4 (III)-3 (I)-7 (1)-4 (III)-7(I)-8 (1)-7 (III)-6 (I)-9 (1)-11 (III)-4 (I)-10 (1)-15 (III)-5 (I)-11(1)-25 (III)-1 (I)-12 (1)-22 (III)-1 (I)-13 (2)-2 (III)-1 (I)-14 (2)-2(III)-3 (I)-15 (2)-2 (III)-7 (I)-16 (2)-3 (III)-4 (I)-17 (2)-3 (III)-7(I)-18 (2)-5 (III)-6 (I)-19 (2)-10 (III)-4 (I)-20 (2)-10 (III)-5 (I)-21(2)-13 (III)-1 (I)-22 (2)-13 (III)-3 (I)-23 (2)-13 (III)-7 (I)-24 (2)-16(III)-5 (I)-25 (2)-23 (III)-7 (I)-26 (2)-23 (III)-4 (I)-27 (2)-25(III)-7 (I)-28 (2)-25 (III)-4 (I)-29 (2)-26 (III)-5 (I)-30 (2)-26(III)-7

TABLE 2 CTM skeleton General Formula Compound structure (III) structure(I)-31 (3)-1 (III)-2 (I)-32 (3)-1 (III)-7 (I)-33 (3)-5 (III)-2 (I)-34(3)-7 (III)-4 (I)-35 (3)-7 (III)-2 (I)-36 (3)-19 (III)-4 (I)-37 (3)-26(III)-1 (I)-38 (3)-26 (III)-3 (I)-39 (4)-3 (III)-3 (I)-40 (4)-3 (III)-4(I)-41 (4)-8 (III)-5 (I)-42 (4)-8 (III)-6 (I)-43 (4)-12 (III)-7 (I)-44(4)-12 (III)-4 (I)-45 (4)-12 (III)-2 (I)-46 (4)-12 (III)-11 (I)-47(4)-16 (III)-3 (I)-48 (4)-16 (III)-4 (I)-49 (4)-20 (III)-1 (I)-50 (4)-20(III)-4 (I)-51 (4)-20 (III)-7 (I)-52 (4)-24 (III)-4 (I)-53 (4)-24(III)-7 (I)-54 (4)-24 (III)-3 (I)-55 (4)-24 (III)-4 (I)-56 (4)-25(III)-1 (I)-57 (4)-26 (III)-3 (I)-58 (4)-28 (III)-4 (I)-59 (4)-28(III)-5 (I)-60 (4)-28 (III)-6 (I)-61 (4)-12 (III)-8

Next, an example of a synthesis pathway of the reactive compound of theexemplary embodiment will be shown below.

Next, specific examples of the novel reactive compound represented byGeneral Formula (I′) will be shown below, but the exemplary embodimentis not limited to the examples.

The “CTM skeleton structure” in the following tables corresponds to thecharge transporting skeleton F in General Formula (I′)

TABLE 3 CTM skeleton General Formula Compound structure (III′) structure(I′)-1 (1)-1 (III′)-1 (I′)-2 (1)-1 (III′)-2 (I′)-3 (1)-1 (III′)-4 (I′)-4(1)-2 (III′)-5 (I′)-5 (1)-2 (III′)-7 (I′)-6 (1)-4 (III′)-3 (I′)-7 (1)-4(III′)-7 (I′)-8 (1)-7 (III′)-6 (I′)-9 (1)-11 (III′)-4 (I′)-10 (1)-15(III′)-5 (I′)-11 (1)-25 (III′)-1 (I′)-12 (1)-22 (III′)-1 (I′)-13 (2)-2(III′)-1 (I′)-14 (2)-2 (III′)-3 (I′)-15 (2)-2 (III′)-7 (I′)-16 (2)-3(III′)-4 (I′)-17 (2)-3 (III′)-7 (I′)-18 (2)-5 (III′)-6 (I′)-19 (2)-10(III′)-4 (I′)-20 (2)-10 (III′)-5 (I′)-21 (2)-13 (III′)-1 (I′)-22 (2)-13(III′)-3 (I′)-23 (2)-13 (III′)-7 (I′)-24 (2)-16 (III′)-5 (I′)-25 (2)-23(III′)-7 (I′)-26 (2)-23 (III′)-4 (I′)-27 (2)-25 (III′)-7 (I′)-28 (2)-25(III′)-4 (I′)-29 (2)-26 (III′)-5 (I′)-30 (2)-26 (III′)-7

TABLE 4 CTM skeleton General Formula Compound structure (III′) structure(I′)-31 (3)-1 (III′)-2 (I′)-32 (3)-1 (III′)-7 (I′)-33 (3)-5 (III′)-2(I′)-34 (3)-7 (III′)-4 (I′)-35 (3)-7 (III′)-2 (I′)-36 (3)-19 (III′)-4(I′)-37 (3)-26 (III′)-1 (I′)-38 (3)-26 (III′)-3 (I′)-39 (4)-3 (III′)-3(I′)-40 (4)-3 (III′)-4 (I′)-41 (4)-8 (III′)-5 (I′)-42 (4)-8 (III′)-6(I′)-43 (4)-12 (III′)-7 (I′)-44 (4)-12 (III′)-4 (I′)-45 (4)-12 (III′)-2(I′)-46 (4)-12 (III′)-11 (I′)-47 (4)-16 (III′)-3 (I′)-48 (4)-16 (III′)-4(I′)-49 (4)-20 (III′)-1 (I′)-50 (4)-20 (III′)-4 (I′)-51 (4)-20 (III′)-7(I′)-52 (4)-24 (III′)-4 (I′)-53 (4)-24 (III′)-7 (I′)-54 (4)-24 (III′)-3(I′)-55 (4)-24 (III′)-4 (I′)-56 (4)-25 (III′)-1 (I′)-57 (4)-26 (III′)-3(I′)-58 (4)-28 (III′)-4 (I′)-59 (4)-28 (III′)-5 (I′)-60 (4)-28 (III′)-6

TABLE 5 CTM skeleton General Formula Compound structure (III′) structure(I′)-61 (1)-1 (III′)-15 (I′)-62 (1)-1 (III′)-27 (I′)-63 (1)-1 (III′)-37(I′)-64 (1)-2 (III′)-52 (I′)-65 (1)-2 (III′)-18 (I′)-66 (1)-4 (III′)-31(I′)-67 (1)-4 (III′)-44 (I′)-68 (1)-7 (III′)-45 (I′)-69 (1)-11 (III′)-45(I′)-70 (1)-15 (III′)-45 (I′)-71 (1)-25 (III′)-15 (I′)-72 (1)-22(III′)-15 (I′)-73 (2)-2 (III′)-15 (I′)-74 (2)-2 (III′)-27 (I′)-75 (2)-2(III′)-37 (I′)-76 (2)-3 (III′)-52 (I′)-77 (2)-3 (III′)-18 (I′)-78 (2)-5(III′)-31 (I′)-79 (2)-10 (III′)-44 (I′)-80 (2)-10 (III′)-45 (I′)-81(2)-13 (III′)-45 (I′)-82 (2)-13 (III′)-45 (I′)-83 (2)-13 (III′)-15(I′)-84 (2)-16 (III′)-15 (I′)-85 (2)-23 (III′)-27 (I′)-86 (2)-23(III′)-37 (I′)-87 (2)-25 (III′)-52 (I′)-88 (2)-25 (III′)-18 (I′)-89(2)-26 (III′)-31 (I′)-90 (2)-26 (III′)-44

TABLE 6 CTM skeleton General Formula Compound structure (III′) structure(I′)-91 (3)-1 (III′)-15 (I′)-92 (3)-1 (III′)-27 (I′)-93 (3)-5 (III′)-37(I′)-94 (3)-7 (III′)-52 (I′)-95 (3)-7 (III′)-18 (I′)-96 (3)-19 (III′)-31(I′)-97 (3)-26 (III′)-44 (I′)-98 (3)-26 (III′)-45 (I′)-99 (4)-3(III′)-45 (I′)-100 (4)-3 (III′)-45 (I′)-101 (4)-8 (III′)-15 (I′)-102(4)-8 (III′)-15 (I′)-103 (4)-12 (III′)-15 (I′)-104 (4)-12 (III′)-27(I′)-105 (4)-12 (III′)-37 (I′)-106 (4)-12 (III′)-52 (I′)-107 (4)-16(III′)-18 (I′)-108 (4)-16 (III′)-31 (I′)-109 (4)-20 (III′)-44 (I′)-110(4)-20 (III′)-45 (I′)-111 (4)-20 (III′)-45 (I′)-112 (4)-24 (III′)-45(I′)-113 (4)-24 (III′)-15 (I′)-114 (4)-24 (III′)-15 (I′)-115 (4)-24(III′)-27 (I′)-116 (4)-25 (III′)-37 (I′)-117 (4)-26 (III′)-52 (I′)-118(4)-28 (III′)-18 (I′)-119 (4)-28 (III′)-31 (I′)-120 (4)-28 (III′)-44(I′)-121 (4)-12 (III′)-8 (I′)-122 (4)-12 (III′)-64 (I′)-123 (4)-12(III′)-1 (I′)-124 (4)-24 (III′)-18 (I′)-125 (4)-24 (III′)-29 (I′)-126(4)-24 (III′)-40 (I′)-127 (4)-24 (III′)-51

An example of a synthesis pathway of the charge transport material (A2)used in the exemplary embodiment will be shown below.

For the composition for forming the charge transporting layer 2B-2, twoor more kinds of the charge transport material (A1) or (A2) of theexemplary embodiment may be used. For example, among the chargetransport material (A1) or (A2), a compound having 4 or more styreneskeletons in total in a molecule and a compound having from 1 to 3styrene skeletons in total in a molecule are concurrently used, thestrength of a polymerized or cured film may be adjusted withoutdeteriorating charge transport performance. In this case, among thecharge transport material (A1) or (A2) of the exemplary embodiment, thecompound having 4 or more styrene skeletons in total in a molecule iscontained desirably at 5% by weight or more, and more desirably at 20%or more, based on the total content of the charge transport material(A1) or (A2) of the exemplary embodiment.

The content of the charge transport material (A1) or (A2) of theexemplary embodiment is desirably 40% by weight or more, more desirably50% by weight or more, and even more desirably 60% by weight or more,based on the total solid content amount of the composition for formingthe charge transporting layer 2B-2.

Next, among components that constitute the composition for forming thecharge transporting layer 2B-2, components other than the chargetransport material (A1) or (A2) of the exemplary embodiment will bedescribed.

The composition for forming the charge transporting layer 2B-2 maycontain a charge transport agent (B) having a chain-polymerizablefunctional group, other than the charge transport material (A1) or (A2)of the exemplary embodiment. Examples of the charge transport agent (B)include compounds disclosed Paragraphs [0060] to [0099] inJP-A-2000-206715, compounds disclosed in Paragraphs [0066] to [0080] inJP-A-2011-70023, and the like. The content of the charge transport agent(B) is generally from 0% by weight to 40% by weight, desirably from 0%by weight to 30% by weight, and more desirably from 0% by weight to 20%by weight, based on the total solid content amount of the compositionfor forming the charge transporting layer 2B-2.

The composition for forming the charge transporting layer 2B-2 maycontain the charge transport material and binder resin that wereexemplified in the description for the charge transporting layer 2B-1.The content of the charge transport material and binder resin isgenerally from 0% by weight to 40% by weight, desirably from 0% byweight to 30% by weight, and more desirably from 0% by weight to 20% byweight, based on the total solid content amount of the composition forforming the charge transporting layer 2B-2.

The composition for forming the charge transporting layer 2B-2 maycontain the following surfactant, in view of securing film formability.

The surfactant includes one or more structures among (A) a structureformed by polymerizing acrylic monomers having a fluorine atom, (B) astructure having a carbon-carbon double bond and a fluorine atom, (C) analkylene oxide structure, and (D) a structure having a carbon-carbontriple bond and a hydroxyl group, in a molecule.

This surfactant may contain one or two or more structures amongstructures (A) to (D), in a molecule.

Hereinafter, the structures (A) to (D) and the surfactants having thesestructures will be described.

(A) Structure Formed by Polymerizing Acrylic Monomers Having a FluorineAtom

Though not particularly limited, the (A) structure formed bypolymerizing acrylic monomers having a fluorine atom is desirably astructure formed by polymerizing acrylic monomers having a fluoroalkylgroup, and more desirably a structure formed by polymerizing acrylicmonomers having a perfluoroalkyl group.

Specific examples of the surfactant having the (A) structure includePolyflow KL-600 (manufactured by Kyoeisha Chemical Co., Ltd), EftopEF-351, Eftop EF-352, Eftop EF-801, Eftop EF-802, and Eftop EF-601(manufactured by JEMCO, Inc.), and the like.

(B) Structure Having Carbon-Carbon Double Bond and Fluorine Atom

Though not particularly limited, the (B) structure having acarbon-carbon double bond and a fluorine atom is desirably a grouprepresented by at least any one of the following Structural Formulae(B1) and (B2).

The surfactant having the (B) structure is desirably a compound having agroup represented by at least any one of the Structural Formulae (B1)and (B2) in a. side chain of an acrylic polymer, or a compoundrepresented by any one of the following Structural Formulae (B3) to(B5).

When the surfactant having the (B) structure is a compound having atleast any one of the Structural Formulae (B1) and (B2) in a side chainof an acrylic polymer, the acrylic structure is easily mixed with othercomponents in the composition, and accordingly, an almost uniformuppermost surface layer may be formed.

When the surfactant having the (B) structure is a compound representedby any one of Structural Formulae (B3) to (B5), cissing caused duringcoating tends to be prevented, and accordingly, defects in a coatingfilm may be inhibited.

In the Structural Formulae (B3) to (B5), each of v and w independentlyrepresents an integer of 1 or greater, R′ represents a hydrogen atom ora monovalent organic group, and each Rf independently represents a grouprepresented by Structural Formula (B1) or (B2).

In Structural Formulae (B3) to (B5), examples of the monovalent organicgroup represented by R′ include an alkyl group having from 1 to 30carbon atoms and a hydroxyalkyl group having from 1 to 30 carbon atoms.

Examples of commercially available products of the surfactant having the(B) structure include the following ones.

Examples of the compound represented by any one of the StructuralFormulae (B3) to (B5) includes Ftergent 100, Ftergent 100C, Ftergent110, Ftergent 140A, Ftergent 150, Ftergent 150CH, Ftergent A-K, Ftergent501, Ftergent 250, Ftergent 251, Ftergent 222F, Ftergent FTX-218,Ftergent 300, Ftergent 310, Ftergent 400SW, Ftergent 212M, Ftergent245M, Ftergent 290M, Ftergent FTX-207S, Ftergent FTX-211S, FtergentFTX-220S, Ftergent FTX-230S, Ftergent FTX-209F, Ftergent FTX-213F,Ftergent FTX-222F, Ftergent FTX-233F, Ftergent FTX-245F, FtergentFTX-208G, Ftergent FTX-218G, Ftergent FTX-230G, Ftergent FTX-240G,Ftergent FTX-204D, Ftergent FTX-280D, Ftergent FTX-212D, FtergentFTX-216D, Ftergent FTX-218D, Ftergent FTX-220D, Ftergent FTX-222D(manufactured by Neos Company Limited), and the like.

Examples of the compound having at least any one of Structural Formulae(B1) and (B2) in a side chain of the acrylic polymer include KB-L82,KB-L85, KB-L97, KB-L109, KB-L110, KB-F2L, KB-F2M, KB-F2S, KB-F3M, KB-FaM(manufactured by Neos Company Limited), and the like.

(C) Alkylene Oxide Structure

(C) alkylene oxide structure includes alkylene oxide and polyalkyleneoxide. Specifically, alkylene oxide includes ethylene oxide, propyleneoxide, and the like. The alkylene oxide structure may be polyalkyleneoxide in which the repeating number of the alkylene oxide is from 2 to10000.

Examples of the surfactant having the (C) alkylene oxide structureinclude polyethylene glycol, a polyether antifoam agent,polyether-modified silicone oil, and the like.

The average molecular weight of the polyethylene glycol is desirably2000 or less, and examples of the polyethylene glycol having an averagemolecular weight of 2000 or less include polyethylene glycol 2000(average molecular weight of 2000), polyethylene glycol 600 (averagemolecular weight of 600), polyethylene glycol 400 (average molecularweight of 400), polyethylene glycol 200 (average molecular weight of200), and the like.

In addition, polyether antifoam agent such as PE-M and PE-L (allmanufactured by Wako Pure Chemical Industries, Ltd.) and an antifoamagents No. 1 and No. 5 (all manufactured by Kao Corporation) are alsoexemplified as suitable examples.

Examples of the surfactant having a fluorine atom in a molecule inaddition to the (C) alkylene oxide structure include a surfactant havingalkylene oxide or polyalkylene oxide in a side chain of a polymer thathas a fluorine atom, a surfactant in which the terminal of alkyleneoxide or polyalkylene oxide is substituted with a substituent that has afluorine atom, and the like.

Specific examples of the surfactant having a fluorine atom in a moleculein addition to the (C) alkylene oxide structure include Megafac F-443,F-444, F-445, and F-446 (all manufactured by DIC Corporation), Ftergent250, Ftergent 251, and Ftergent 222F (all manufactured by Neos CompanyLimited), POLY FOX PF636, PF6320, PF6520, and PF656 (all manufactured byKitamura Chemicals Co., Ltd.), and the like.

Specific examples of the surfactant having a silicone structure in amolecule in addition to the (C) alkylene oxide structure include KF351(A), KF352 (A), KF353 (A), KF354 (A), KF355 (A), KF615 (A), KF618, KF945(A), and KF6004 (all manufactured by Shin-Etsu Chemical Co., Ltd.),TSF4440, TSF4445, TSF4450, TSF4446, TSF4452, TSF4453, and TSF4460 (allmanufactured by GE Toshiba Silicones, Co., Ltd.), BYK-300, 302, 306,307, 310, 315, 320, 322, 323, 325, 330, 331, 333, 337, 341, 344, 345,346, 347, 348, 370, 375, 377, 378, UV3500, UV3510, and UV3570 (allmanufactured by BYK-Chemie Japan KK), and the like.

(D) Structure Having Carbon-Carbon Triple Bond and Hydroxyl Group

(D) structure having a carbon-carbon triple bond and a hydroxyl group isnot particularly limited, and examples of the surfactant having thisstructure include the following compounds.

Examples of the surfactant having the (D) structure including acarbon-carbon triple bond and a hydroxyl group include a compound havinga triple bond and a hydroxyl group in a molecule, and specific examplesthereof include 2-propyn-1-ol, 1-butyn-3-ol, 2-butyn-1-ol, 3-butyn-1-ol,1-pentyn-3-ol, 2-pentyn-1-ol, 3-pentyn-1-ol, 4-pentyn-1-ol,4-pentyn-2-ol, 1-hexyn-3-ol, 2-hexyn-1-ol, 3-hexyn-1-ol, 5-hexyn-1-ol,5-hexyn-3-ol, 1-heptyn-3-ol, 2-heptyn-1-ol, 3-heptyn-1-ol,4-heptyn-2-ol, 5-heptyn-3-ol, 1-octyn-3-ol, 3-octyn-1-ol, 3-nonyn-1-ol,2-decyn-1-ol, 3-decyn-1-ol, 10-undecyn-1-ol, 3-methyl-1-butyn-3-ol,3-methyl-1-penten-4-yn-3-ol, 3-methyl-1-pentyn-3-ol,5-methyl-1-hexyn-3-ol, 3-ethyl-1-pentyn-3-ol, 3-ethyl-1-heptyn-3-ol,4-ethyl-1-octyn-3-ol, 3,4-dimethyl-1-pentyn-3-ol,3,5-dimethyl-1-hexyn-3-ol, 3,6-dimethyl-1-heptyn-3-ol,2,2,8,8-tetramethyl-3,6-nonadiyn-5-ol, 4,6-nonadecadiyn-1-ol,10,12-pentacosadiyn-1-ol, 2-butyne-1,4-diol, 3-hexyne-2,5-diol,2,4-hexadiyne-1,6-diol, 2,5-dimethyl-3-hexyne-2,5-diol,3,6-dimethyl-4-octyne-3,6-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol,(+)-1,6-bis(2-chlorophenyl)-1,6-diphenyl-2,4-hexadiyne-1,6-diol,(−)-1,6-bis(2-chlorophenyl)-1,6-diphenyl-2,4-hexadiyne-1,6-diol,2-butyne-1,4-diol bis(2-hydroxyethyl), 1,4-diacetoxy-2-butyne,4-diethylamino-2-butyn-1-ol, 1,1-diphenyl-2-propyn-1-ol,1-ethynyl-1-cyclohexanol, 9-ethynyl-9-fluorenol,2,4-hexadiynediol-1,6-bis(4-phenylazobenzenesulfonate),2-hydroxy-3-butynic acid, 2-hydroxy-3-butynic acid ethyl ester,2-methyl-4-phenyl-3-butyn-2-ol, methyl propargyl ether,5-phenyl-4-pentyn-1-ol, 1-phenyl-1-propyn-3-ol, 1-phenyl-2-propyn-1-ol,4-trimethylsilyl-3-butyn-2-ol, 3-trimethylsilyl-2-propyn-1-ol, and thelike.

The examples also include a compound (for example a Surfynol 400 series(manufactured by Shin-Etsu Chemical Co., Ltd.)) obtained by addingalkylene oxide such as ethylene oxide to a portion or all of hydroxylgroups in the above compound, and the like.

As the surfactant having the (D) structure including a carbon-carbontriple bond and a hydroxyl group, compounds represented by any one ofthe following General Formulae (D1) and (D2) are desirable.

In General Formulae (D1) and (D2), each of R^(a), R^(b), R^(c), andR^(d) independently represents a monovalent organic group, and each ofx, y, and z independently represents an integer of 1 or greater.

Among the compounds represented by General Formula (D1) or (D2),compounds in which R^(a), R^(b), and R^(d) are alkyl groups aredesirable, and compounds in which at least one of R^(a) and R^(b) and atleast one of R^(c) and R^(d) is a branched alkyl group are moredesirable. z is desirably from 1 to 10, and each of x and y is desirablyfrom 1 to 500.

Examples of commercially available products of the compound representedby General Formula (D1) or (D2) include a Surfynol 400 series(manufactured by Shin-Etsu Chemical Co., Ltd.).

The surfactant having the structure of (A) to (D) described above may beused alone or used as a mixture of plural kinds thereof. When thesurfactant is used as a mixture of plural kinds thereof, a surfactanthaving a structure differing from that of the surfactant having thestructure of (A) to (D) may be concurrently used, within a range thatdoes not impair the effect of the exemplary embodiment.

Examples of the surfactant that may be concurrently used include thefollowing surfactants having a fluorine atom and surfactants having asilicone structure.

That is, suitable examples of the surfactant that has a fluorine atomand may be concurrently used with the surfactant having the structure of(A) to (D) include perfluoroalkyl sulfonic acids (for example,perfluorobutane sulfonic acid, perfluorooctane sulfonic acid, and thelike), perfluoroalkyl carboxylic acids (for example, perfluorobutanecarboxylic acid, perfluorooctane carboxylic acid, and the like), andperfluoroalkyl group-containing phosphoric acid ester. Theperfluoroalkyl sulfonic acids and perfluoroalkyl carboxylic acids may bea salt thereof and an amide-modified product thereof.

Examples of commercially available products of the perfluoroalkylsulfonic acids include Megafac F-114 (manufactured by DIC Corporation),Eftop EF-101, Eftop EF-102, Eftop EF-103, Eftop EF-104, Eftop EF-105,Eftop EF-112, Eftop EF-121, Eftop EF-122A, Eftop EF-122B, Eftop EF-122C,and Eftop EF-123A (manufactured by JEMCO, Inc.), Ftergent 100, Ftergent100C, Ftergent 110, Ftergent 140A, Ftergent 150, Ftergent 150CH,Ftergent A-K, and Ftergent 501 (manufactured by Neos Company Limited),and the like.

Examples of commercially available products of the perfluoroalkylcarboxylic acids include Megafac F-410 (manufactured by DICCorporation), Eftop EF-201 and Eftop EF-204 (manufactured by JEMCO,Inc.), and the like.

Examples of commercially available products of the perfluoroalkylgroup-containing phosphoric acid ester include Megafac F-493 and MegafacF-494 (manufactured by DIC Corporation), Eftop EF-123A, Eftop EF-123B,Eftop EF-125M, and Eftop EF-132 (manufactured by JEMCO, Inc.), and thelike.

The surfactant that has a fluorine atom and may be concurrently usedwith the surfactant having the structure of (A) to (D) is not limited tothe above-described surfactants. For example, a fluorine atom-containingcompound having a betaine structure (for example, Ftergent 400SWmanufactured by Neos Company Limited) and a surfactant having anamphoteric ion group (for example, Ftergent SW manufactured by NeosCompany Limited) are also suitably used as the surfactant.

Examples of the surfactant that has a silicone structure and may beconcurrently used with the surfactant having the structure of (A) to (D)include general silicone oil such as dimethyl silicone, methyl phenylsilicone, diphenyl silicone, or a derivative thereof.

The content of the surfactant is desirably from 0.01% by weight to 1% byweight, and more desirably from 0.02% by weight to 0.5% by weight, basedon the total solid content amount of the composition for forming thecharge transporting layer 2B-2. If the content of the surfactant is lessthan 0.01% by weight, the effect of preventing defects in coating filmtends to be insufficient. If the content of the surfactant exceeds 1% byweight, the surfactant and curing components (compound represented byGeneral Formula (I) and other monomer, oligomer, and the like) areseparated from each other, and consequently, the strength of theobtained polymerized or cured film tends to be reduced.

In addition, among all surfactants, the surfactant having the structureof (A) to (D) is contained in the composition desirably at 1% by weightor more, and more desirably at 10% by weight or more.

For the purpose of controlling the viscosity of the composition and thestrength, flexibility, smoothness, a cleaning property, and the like ofthe film, a radical-polymerizable monomer, oligomer, or the like thatdoes not have a charge transport function may be added to thecomposition used for forming the charge transporting layer 2B-2.

Examples of a monofunctional radical-polymerizable monomer includeisobutyl acrylate, t-butyl acrylate, isooctyl acrylate, lauryl acrylate,stearyl acrylate, isobornyl acrylate, cyclohexyl acrylate,2-methoxyethyl acrylate, methoxy triethylene glycol acrylate,2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate,ethyl carbitol acrylate, phenoxyethyl acrylate, 2-hydroxy acrylate,2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, methoxy polyethyleneglycol acrylate, methoxy polyethylene glycol methacrylate, phenoxypolyethylene glycol acrylate, phenoxy polyethylene glycol methacrylate,hydroxyethyl o-phenylphenol acrylate, o-phenylphenol glycidyl etheracrylate, and the like.

Examples of a bifunctional radical-polymerizable monomer include1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanedioldiacrylate, 2-n-butyl-2-ethyl-1,3-propanediol diacrylate, tripropyleneglycol diacrylate, tetraethylene glycol diacrylate, dioxane glycoldiacrylate, polytetramethylene glycol diacrylate, ethoxylated bisphenolA diacrylate, ethoxylated bisphenol A dimethacrylate, tricyclodecanemethanol diacrylate, tricyclodecane methanol dimethacrylate, divinylbenzene, diallyl propyl isocyanurate, and the like.

Examples of a tri- or higher functional radical-polymerizable monomerinclude trimethylolpropane triacrylate, trimethylolpropanetrimethacrylate, pentaerythritol acrylate, trimethylolpropane EO-addedtriacrylate, glycerin PO-added triacrylate, trisacryloyloxy ethylphosphate, pentaerythritol tetraacrylate, ethoxylated isocyanurtriacrylate, triallyl isocyanurate, trivinyl cyclohexane, trivinylbenzene, and the like.

Examples of a radical-polymerizable oligomer include oligomers based onepoxy acrylate, urethane acrylate, and polyester acrylate.

The radical-polymerizable monomer or oligomer that does not have acharge transport function is desirably contained in the composition atfrom 0% by weight to 50% by weight, more desirably from 0% by weight to40% by weight, and even more desirably from 0% by weight to 30% byweight, based on the total solid content of the composition.

The cured film (crosslinked film) configuring the charge transportinglayer 2B-2 is obtained by curing the composition containing therespective components through various methods such as heat, light, andelectron beams. If necessary, a thermal polymerization initiator or aphotopolymerization initiator may be added to the composition.

In order to keep balance between characteristics such as mechanicalstrength, thermal curing is desirable. Usually, when a general acryliccoating material or the like is cured, electron beams that cure thematerial without using a catalyst or photopolymerization that cures thematerial in a short time is suitably used. However, in anelectrophotographic photoreceptor, since a photosensitive layer, whichis the surface to be formed, of an uppermost surface layer containsphotosensitive materials, it is desirable to perform thermal curing inwhich the reaction proceeds slowly, in order that the photosensitivematerials are not easily damaged and that the surface properties of theobtained cured film are improved. Thermal curing may be performedwithout a catalyst, but it is desirable to use a thermal radicalinitiator as a catalyst.

The thermal radical initiator is not particularly limited. However, inorder to inhibit the photosensitive materials in the photosensitivelayer from being damaged during the formation of the charge transportinglayer 2B-2, a thermal radical initiator having a 10-hour half lifetemperature of from 40° C. to 110° C. is desirable.

Examples of commercially available products of the thermal radicalinitiator include azo-based initiators such as V-30, (10-hour half lifetemperature: 104° C.), V-40 (10-hour half life temperature: 88° C.),V-59 (10-hour half life temperature: 67° C.), V-601 (10-hour half lifetemperature: 66° C.), V-65 (10-hour half life temperature: 51° C.), V-70(10-hour half life temperature: 30° C.), VF-096 (10-hour half lifetemperature: 96° C.), Vam-110 (10-hour half life temperature: 111° C.),Vam-111 (10-hour half life temperature: 111° C.), VE-073 (10-hour halflife temperature: 73° C.)(all manufactured by Wako Pure ChemicalIndustries, Ltd.), OTAZO-15 (10-hour half life temperature: 61° C.),OTAZO-30 (10-hour half life temperature: 57° C.), AIBN (10-hour halflife temperature: 65° C.), AMBN (10-hour half life temperature: 67° C.),ADVN (10-hour half life temperature: 52° C.), and ACVA (10-hour halflife temperature: 68° C.) (all manufactured by Otsuka Chemical Co.,Ltd.); Pertetra A, Perhexa HC, Perhexa C, Perhexa V, Perhexa 22, PerhexaMC, Perbutyl H, Percumyl H, Percumyl P, Permenta H, Perocta H, PerbutylC, Perbutyl D, Perhexyl D, Peroyl IB, Peroyl 355, Peroyl L, Peroyl SA,Nyper BW, Nyper BMT-K40/M, Peroyl IPP, Peroyl NPP, Peroyl TCP, PeroylOPP, Peroyl SBP, Percumyl ND, Perocta ND, Perhexyl ND, Perbutyl ND,Perbutyl NHP, Perhexyl PV, Perbutyl PV, Perhexa 250, Perocta O, PerhexylO, Perbutyl O, Perbutyl L, Perbutyl 355, Perhexyl I, Perbutyl I,Perbutyl E, Perhexa 25Z, Perbutyl A, Perhexyl Z, Perbutyl ZT, andPerbutyl Z (all manufactured by Nof Corporation); Kayaketal AM-055,Trigonox 36-C75, Laurox, Perkadox L-W75, Perkadox CH-50L, Trigonox TMBH,Kayacumene H, Kayabutyl H-70, Perkadox BC-FF, Kayahexa AD, Perkadox 14,Kayabutyl C, Kayabutyl D, Kayahexa YD-E85, Perkadox 12-XL25, Perkadox12-EB20, Trigonox 22-N70, Trigonox 22-70E, Trigonox D-T50, Trigonox423-C70, Kayaester CND-C70, Kayaester CND-W50, Trigonox 23-C70, Trigonox23-W50N, Trigonox 257-C70, Kayaester P-70, Kayaester TMPO-70, Trigonox121, Kayaester O, Kayaester HTP-65W, Kayaester AN, Trigonox 42, TrigonoxF-050, Kayabutyl B, Kayacarbon EH-C70, Kayacarbon EH-W60, Kayacarbon1-20, Kayacarbon BIC-75, Trigonox 117, and Kayalene 6-70 (manufacturedby Kayaku Akzo Co., Ltd.); Luperox LP (10-hour half life temperature:64° C.), Luperox 610 (10-hour half life temperature: 37° C.), Luperox188 (10-hour half life temperature: 38° C.), Luperox 844 (10-hour halflife temperature: 44° C.), Luperox 259 (10-hour half life temperature:46° C.), Luperox 10 (10-hour half life temperature: 48° C.), Luperox 701(10-hour half life temperature: 53° C.), Luperox 11 (10-hour half lifetemperature: 58° C.), Luperox 26 (10-hour half life temperature: 77°C.), Luperox 80 (10-hour half life temperature: 82° C.), Luperox 7(10-hour half life temperature: 102° C.), Luperox 270 (10-hour half lifetemperature: 102° C.), Luperox P (10-hour half life temperature: 104°C.), Luperox 546 (10-hour half life temperature: 46° C.), Luperox 554(10-hour half life temperature: 55° C.), Luperox 575 (10-hour half lifetemperature: 75° C.), Luperox TANPO (10-hour half life temperature: 96°C.), Luperox 555 (10-hour half life temperature: 100° C.), Luperox 570(10-hour half life temperature: 96° C.), Luperox TAP (10-hour half lifetemperature: 100° C.), Luperox TBIC (10-hour half life temperature: 99°C.), Luperox TBEC (10-hour half life temperature: 100° C.), Luperox JW(10-hour half life temperature: 100° C.), Luperox TAIC (10-hour halflife temperature: 96° C.), Luperox TAEC (10-hour half life temperature:99° C.), Luperox DC (10-hour half life temperature: 117° C.), Luperox101 (10-hour half life temperature: 120° C.), Luperox F (10-hour halflife temperature: 116° C.), Luperox D1 (10-hour half life temperature:129° C.), Luperox 130 (10-hour half life temperature: 131° C.), Luperox220 (10-hour half life temperature: 107° C.), Luperox 230 (10-hour halflife temperature: 109° C.), Luperox 233 (10-hour half life temperature:114° C.), and Luperox 531 (10-hour half life temperature: 93° C.) (allmanufactured by ARKEMA YOSHITOMI, LTD.); and the like.

The thermal radical initiator may be contained in the composition atfrom 0.001% by weight to 10% by weight, more desirably from 0.01% byweight to 5% by weight, and even more desirably from 0.1% by weight to3% by weight, based on the reactive compound in the composition.

When the charge transporting layer 2B-2 is formed by photocuring, knownphotopolymerization initiators are used. Examples of the photo-radicalinitiator include an intramolecular cleavage type catalyst, a hydrogenabstraction type catalyst, and the like.

Examples of the intramolecular cleavage type catalyst include catalystsbased on benzylketal, alkylphenone, aminoalkylphenone, phosphine oxide,titanocene, and oxime.

Specific examples of the benzylketal-based catalyst include2,2-dimethoxy-1,2-diphenylethan-1-one. Examples of thealkylphenone-based catalyst include 1-hydroxy-cyclohexyl-phenyl-ketone,2-hydroxy-2-methyl-1-phenyl-propan-1-one,1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one,2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one,acetophenone, and 2-phenyl-2-(p-toluenesulfonyloxy)acetophenone.Examples of the aminoalkylphenone-based catalyst includep-dimethylaminoacetophenone, p-dimethylaminopropiophenone,2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone,and the like. Examples of the phosphine oxide-based catalyst include2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide,bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and the like.Examples of the titanocene-based catalyst includebis(η5-2,4-cyclopentadiene-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titaniumand the like. Examples of the oxime-based catalyst include1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone,1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl, 1-(0-acetyloxime) andthe like.

Examples of the hydrogen abstraction type catalyst include catalystsbased on benzophenone, thioxanthone, benzyl, Michler ketone, and thelike.

Specific examples of the benzophenone-based catalyst include 2-benzoylbenzoate, 2-chlorobenzophenone, 4,4′-dichlorobenzophenone, 4-benzoyl4′-methyldiphenyl sulfide, p,p′-bisdiethylaminobenzophenone, and thelike. Examples of the thioxanthone-based catalyst include2,4-diethylthioxanthen-9-one, 2-chlorothioxanthone,2-isopropylthioxanthone, and the like. Examples of the benzyl-based typecatalyst include benzyl, (±)-camphorquinone, p-anisil, and the like.

The photo-radical initiator is contained in the composition desirably atfrom 0.001% by weight to 10% by weight, more desirably from 0.01% byweight to 5% by weight, and even more desirably from 0.1% by weight to3% by weight, based on the reactive compound in the composition.

To the composition used for forming the charge transporting layer 2B-2,other thermosetting resins such as a phenol resin, a melamine resin, anda benzoguanamine resin may be added, in order that oxidation caused bygas generated by discharge is effectively inhibited by these resinswhich are added to keep the composition from adsorbing too much gasgenerated by discharge.

In addition, for the purpose of adjusting film formability, flexibility,smoothness, and adhesiveness of the film, a coupling agent, a hardcoating agent, and a fluorine-containing compound may be further addedto the composition used for forming the charge transporting layer 2B-2.Specifically, as these additives, various silane coupling agents andcommercially available silicone-based hard coating agents are used.

As the silane coupling agents, vinyl trichlorosilane, vinyltrimethoxysilane, vinyl triethoxysilane, glycidoxypropyl methyldiethoxysilane, γ-glycidoxypropyl trimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminopropyl methyldimethoxysilane, N-β(aminoethyl) γ-aminopropyl triethoxysilane,tetramethoxysilane, methyl trimethoxysilane, dimethyl dimethoxysilane,and the like are used.

As the commercially available hard coating agents, KP-85, X-40-9740, andX-8239 (all manufactured by ShinEtsu Silicones); AY42-440, AY42-441, andAY49-208 (all manufactured by Dow Corning Toray); and the like are used.

In addition, in order to impart water repellency or the like,fluorine-containing compounds such as(tridecafluoro-1,1,2,2-tetrahydrooctyl)triethoxysilane,(3,3,3-trifluoropropyl)trimethoxysilane, 3-(heptafluoroisopropoxy)propyltriethoxysilane, 1H,1H,2H,2H-perfluoroalkyl triethoxysilane,1H,1H,2H,2H-perfluorodecyl triethoxysilane, and1H,1H,2H,2H-perfluoroctyl triethoxysilane may also be added.

The silane coupling agent is used in an arbitrary amount, but the amountof the fluorine-containing compound is desirably 0.25 time or less ofthe compound not containing fluorine in terms of a weight ratio, in viewof the formability of the crosslinked film.

For the purposes of adjusting the discharge gas resistance, mechanicalstrength, and damage resistance of the charge transporting layer 2B-2,reducing torque, controlling abrasion loss, and extending pot life, orfor the purposes of controlling particle dispersibility and viscosity, athermoplastic resin may be added to the composition used for forming thecharge transporting layer 2B-2.

Examples of the thermoplastic resin include a polyvinyl butyral resin, apolyvinyl formal resin, a polyvinyl acetal resin (for example S-LEC B,K, and the like manufactured by Sekisui Chemical Co., Ltd.) such as apartially acetalized polyvinyl acetal resin obtained when a portion ofbutyral is modified with formal, acetoacetal, or the like, a polyamideresin, a cellulose resin, a polyvinyl phenol resin, and the like.Particularly, in view of electrical characteristics, a polyvinyl acetalresin and a polyvinyl phenol resin are desirable. The weight averagemolecular weight of the resin is desirably from 2,000 to 100,000, andmore desirably from 5,000 to 50,000. If the molecular weight of theresin is less than 2,000, the effect produced by the addition of theresin tends to be insufficient. If the molecular weight exceeds 100,000,solubility decreases, the amount of the resin added is restricted, and adefective film tends to be formed when the composition is coated. Theamount of the resin added is desirably from 1% by weight to 40% byweight, more desirably from 1% by weight to 30% by weight, and even moredesirably from 5% by weight to 20% by weight. If the amount of the resinadded is less than 1% by weight, the effect produced by the addition ofthe resin tends to be insufficient, and if it exceeds 40% by weight,image blurring easily occurs at a high temperature and high humidity(for example, 28° C. and 85% RH).

For the purpose of preventing the deterioration of the chargetransporting layer 2B-2 caused by oxidizing gas such as ozone which isgenerated by a charging device, it is desirable to add an antioxidant tothe composition used for forming the charge transporting layer 2B-2. Ifthe mechanical strength of the photoreceptor surface increases, and thelife of the photoreceptor is extended, the photoreceptor contacts theoxidizing gas for a long time. Accordingly, oxidation resistancestronger than that in the related art is required.

As the antioxidant, antioxidants based on hindered phenol or hinderedamine are desirable, and known antioxidants such as an organicsulfur-based antioxidant, a phosphite-based antioxidant, adithiocarbamic acid salt-based antioxidant, a thiourea-basedantioxidant, and a benzimidazole-based antioxidant may also be used. Theamount of the antioxidant added is desirably 20% by weight or less, andmore desirably 10% by weight or less.

Examples of the hindered phenol-based antioxidant include2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butylhydroquinone,N,N′-hexamethylenebis(3,5-di-t-butyl-4-hydroxyhydrocinnamide,3,5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester,2,4-bis[(octylthio)methyl]-o-cresol, 2,6-di-t-butyl-4-ethylphenol,2,2′-methylenebis(4-methyl-6-t-butylphenol),2,2′-methylenebis(4-ethyl-6-t-butylphenol),4,4′-butylidenebis(3-methyl-6-t-butylphenol), 2,5-di-t-amylhydroquinone,2-t-butyl-6-(3-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate,4,4′-butylidenebis(3-methyl-6-t-butylphenol), and the like.

For the purpose of decreasing the residual potential of the chargetransporting layer 2B-2 or improving the strength of the chargetransporting layer 2B-2, various particles may be added to thecomposition used for forming the charge transporting layer 2B-2.

An example of the particles includes silicon-containing particles. Thesilicon-containing particles are particles containing silicon as aconstituent element, and specific examples thereof include colloidalsilica, silicone particles, and the like. The colloidal silica used asthe silicon-containing particles is selected from those obtained bydispersing silica having an average particle size of from 1 nm to 100 nmand desirably from 10 nm to 30 nm in an organic solvent such as anacidic or alkaline aqueous dispersion, an alcohol, a ketone, or anester, and commercially available general colloidal silica may also beused. The solid content of the colloidal silica contained in the chargetransporting layer 2B-2 is not particularly limited. However, thecolloidal silica is used in a range of from 0.1% by weight to 50% byweight, and desirably in a range of from 0.1% by weight to 30% byweight, based on the total solid content amount of the chargetransporting layer 2B-2, in respect of film formability, electricalcharacteristics, and strength.

The silicone particles used as the silicon-containing particles areselected from silicone resin particles, silicone rubber particles, andsilica particles that are surface-treated with silicone, andcommercially available general silicone particles are used. Thesesilicone particles are spherical, and the average particle size thereofis desirably from 1 nm to 500 nm, and more desirably from 10 nm to 100nm. The silicone particles are small size particles that are chemicallyinactive and have excellent dispersibility with a resin. The amount ofthe silicone particles added that is required for obtaining moresufficient characteristics is small. Accordingly, the surface propertiesof the electrophotographic photoreceptor are improved without hinderinga crosslinking reaction. That is, while these particles are incorporatedin a strong crosslinked structure without variation, the lubricity andwater repellency of the electrophotographic photoreceptor surface areimproved, and excellent abrasion resistance and a contaminant-repellingproperty are maintained over a long time.

The content of the silicone particles in the charge transporting layer2B-2 is desirably from 0.1% by weight to 30% by weight, and moredesirably from 0.5% by weight to 10% by weight, based on the total solidcontent amount of the charge transporting layer 2B-2.

Examples of other particles include fluorine-based particles such astetrafluoroethylene, trifluoroethylene, hexafluoropropylene, vinylfluoride, vinylidene fluoride; particles including a resin that isobtained by copolymerizing a fluororesin with a monomer having ahydroxyl group, as disclosed in “Proceedings of the 8^(th) PolymerMaterial Forum, 89”; and semiconductive metallic oxides such asZnO—Al₂O₃, SnO₂—Sb₂O₃, In₂O₃—SnO₂, ZnO₂—TiO₂, ZnO—TiO₂, MgO—Al₂O₃,FeO—TiO₂, TiO₂, SnO₂, In₂O₃, ZnO, and MgO. For the same purpose asdescribed above, oil such as silicone oil may be added. Examples of thesilicone oil include silicone oil such as dimethyl polysiloxane,diphenyl polysiloxane, or phenyl methyl siloxane; reactive silicone oilsuch as amino-modified polysiloxane, epoxy-modified polysiloxane,carboxyl-modified polysiloxane, carbinol-modified polysiloxane,methacryl-modified polysiloxane, mercapto-modified polysiloxane, orphenol-modified polysiloxane; cyclic dimethyl cyclosiloxanes such ashexamethyl cyclotrisiloxane, octamethyl cyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethyl cyclohexasiloxane; cyclicmethylphenyl cyclosiloxanes such as 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenylcyclotetrasiloxane, and 1,3,5,7,9-pentamethyl-1,3,5,7,9-pentaphenylcyclopentasiloxane; cyclic phenyl cyclosiloxanes such as hexaphenylcyclotrisiloxane; fluorine-containing cyclosiloxanes such as(3,3,3-trifluoropropyl)methyl cyclotrisiloxane; hydrosilylgroup-containing cyclosiloxanes such as a methyl hydrosiloxane mixture,pentamethyl cyclopentasiloxane, and phenyl hydrocyclosiloxane; vinylgroup-containing cyclosiloxanes such as pentavinyl pentamethylcyclopentasiloxane; and the like.

A metal, metallic oxide, carbon black, and the like may also be added tothe composition used for forming the charge transporting layer 2B-2.Examples of the metal include aluminum, zinc, copper, chromium, nickel,silver and stainless steel, or those obtained by vapor-depositing thesemetals onto the surface of plastic particles. Examples of the metallicoxide include zinc oxide, titanium oxide, tin oxide, antimony oxide,indium oxide, bismuth oxide, indium oxide doped with tin, tin oxidedoped with antimony or tantalum, zirconium oxide doped with antimony,and the like. These metallic oxides may be used alone or in combinationof two or more kinds thereof. When used in combination of two or morekinds thereof, the metallic oxide may be simply mixed, or may be used inthe form of a solid solution or may be melted. The average particle sizeof the conductive particles is 0.3 μm or less, and particularlydesirably 0.1 μm or less, in view of the transparency of the chargetransporting layer 2B-2.

The composition used for forming the charge transporting layer 2B-2 isdesirably prepared as a coating liquid for forming the chargetransporting layer 2B-2. This coating liquid may be free of a solvent,or if necessary, this coating liquid may contain a solvent includingaromatic hydrocarbons such as toluene, xylene, and chlorobenzene;alcohols such as methanol, ethanol, propanol, butanol, cyclopentanol,cyclohexanol; ketones such as acetone, methyl ethyl ketone, and methylisobutyl ketone; ethers such as tetrahydrofuran, diethyl ether,diisopropyl ester, and dioxane; esters such as ethyl acetate, n-propylacetate, n-butyl acetate, ethyl lactate; and the like.

These solvents may be used alone or used as a mixture of two or morekinds thereof, and a boiling point of the solvent is desirably 100° C.or lower.

In addition, for the purpose of improving storage stability of thecoating liquid for forming the charge transporting layer 2B-2, apolymerization inhibitor may be contained in the coating liquid. As thepolymerization inhibitor, known ones are used. The hindered phenol orhindered amine-based antioxidants exemplified above as specific examplesof the antioxidants also function as the polymerization inhibitor, sothese may be favorably used.

The coating liquid used for forming the charge transporting layer 2B-2that contains the composition used for forming the charge transportinglayer 2B-2 is coated onto a surface to be coated (the surface of chargetransporting layer 2B-1 in the first embodiment shown in FIG. 1) on thecharge transporting layer 2B-1 by general methods such as blade coating,wire bar coating, spray coating, dip coating, bead coating, air knifecoating, and curtain coating, and cured (polymerized) if necessary bybeing heated at, for example, from 100° C. to 170° C., thereby obtaininga polymerized or cured film. In this manner, the charge transportinglayer 2B-2 (corresponding to the layer (Oc1) of the exemplary embodimentin the first embodiment) including this polymerized or cured film isobtained.

The oxygen concentration in the coating liquid for forming the chargetransporting layer 2B-2 during curing is desirably 1% or less, moredesirably 1000 ppm or less, and even more desirably 500 ppm or less.

The coating liquid for forming the charge transporting layer 2B-2 isused not only for the photoreceptor, but also for an antistatic film of,for example, a fluorescence coating material, a glass surface, and aplastic surface. If this coating liquid is used, a coat having excellentadhesiveness with respect to the underlayer is formed, and performancedeterioration caused by repeated use over a long time is inhibited.

—Charge Transporting Layer 2B (Corresponding to Layer (Oc2) of ExemplaryEmbodiment in the Second Embodiment)—

The charge transporting layer 2B may have the same configuration as thatof the charge transporting layer 2B-2 in the first embodiment. Thecomposition for forming the charge transporting layer 2B and the methodof forming this layer are the same as those in the case of the chargetransporting layer 2B-2.

—Single Layer Type Photosensitive Layer 6 (Corresponding to Layer (Oc3)of Exemplary Embodiment in the Third Embodiment)—

So far, as the electrophotographic photoreceptor, a functionalseparation type has been described for example. The content of thecharge generating material in the single layer type photosensitive layer6 (charge generating/charge transporting layer) shown in FIG. 3 is from10% by weight to 85% by weight, and desirably from 20% by weight to 50%by weight. In addition, the content of the charge transport material isdesirably from 5% by weight to 50% by weight.

The method of forming the single layer type photosensitive layer 6(charge generating/charge transporting layer) is the same as that of thecharge generating layer 2A and the charge transporting layer 2B-2. Thefilm thickness of the single layer type photosensitive layer (chargegenerating/charge transporting layer) 6 is desirably from 5 μm to 50 μm,and more desirably from 10 μm to 40 μm.

In the above exemplary embodiment, an embodiment was described in whichthe uppermost surface layer (charge transporting film) including thepolymerized or cured film of the composition containing the chargetransport material (A1) or (A2) is a charge transporting layer or aphotosensitive layer. However, when a protective layer is provided asthe uppermost surface layer on the charge transporting layer orphotosensitive layer, the protective layer may be configured with apolymerized or cured film of the composition containing the chargetransport material (A1) or (A2).

In addition, in the exemplary embodiment described above, an embodimentwas described in which a polymerized or cured film (charge transportingfilm) of the composition containing the charge transport material (A1)or (A2) of the exemplary embodiment is applied as the uppermost surfacelayer of the electrophotographic photoreceptor. However, the polymerizedor cured film containing the charge transport material (A1) or (A2) ofthe exemplary embodiment is not limited to this embodiment. The curedfilm containing the charge transport material (A1) or (A2) of theexemplary embodiment is also applied to, for example, anelectroluminescence (EL) element, a memory device, and a wavelengthconversion element. Moreover, it is considered that the cured filmaccording to the exemplary embodiment is formed without impairing thecharge transport property. Accordingly, this film does not exhibitmorphological change which is caused by Joule heat and is observed inthe charge transporting film in the related art, and has excellent filmformability at the time of lamination. Consequently, this cured film isuseful for the above-described purposes.

[Photoelectric Conversion Device]

The photoelectric conversion device according to the exemplaryembodiment is characterized by including the charge transporting filmaccording to the exemplary embodiment described above.

As described above, the charge transporting film according to theexemplary embodiment is excellent in both the mechanical strength andcharge transport performance. Therefore, this film may be suitablyapplied to a layer which needs to have mechanical strength in aphotoelectric conversion device.

Examples of the photoelectric device according to the exemplaryembodiment include an electrophotographic photoreceptor, an organic ELdevice, an organic transistor, an organic solar cell, and the like.

Specifically, for example, the organic EL device is configured with apair of electrodes in which at least one of the electrodes istransparent or semitransparent, and one or plural organic compoundlayers interposed between these electrodes. The charge transporting filmaccording to the exemplary embodiment of the invention may be used forat least one of the organic compound layers, and the layer configurationthereof is not particularly limited. Specifically, the chargetransporting film according to the exemplary embodiment is applied as aluminous layer, a hole transporting layer, and a hole injecting layer.

In addition, for example, an organic thin film transistor includes anorganic semiconductor layer that contacts both a source electrode and adrain electrode facing to each other, a gate electrode that is separatedfrom both the source electrode and drain electrode, and an insulatinglayer disposed between the organic semiconductor layer and the gateelectrode. The charge transporting film according to the exemplaryembodiment of the invention may be used for at least one of the organicsemiconductor layers, and the layer configuration thereof is notparticularly limited.

EXAMPLES

Hereinafter, the invention will be described in more detail based onexamples, but the invention is not limited thereto.

Synthesis Example 1-1

—Synthesis of Charge Transport Agent (I)-7 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 32.6 g of 3,4-dimethylacetanilide, 56.0 gof 4-iodobiphenyl, 30.4 g of potassium carbonate, 1.5 g of coppersulfate pentahydrate, and 50 ml of n-tridecane are added, and thismixture is stirred for 20 hours while being heated at 220° C. undernitrogen flow. Thereafter, the temperature is reduced to 120° C., andthen 50 ml of ethylene glycol and an aqueous potassium hydroxidesolution (potassium hydroxide 15.7 g/water 20 ml) are added thereto,followed by stirring for another 6 hours. Subsequently, the temperatureis reduced to room temperature, and 200 ml of toluene and 150 ml ofwater are added thereto, thereby performing liquid separation. A toluenelayer is collected, 20 g of sodium sulfate is added thereto, followed bystirring for 10 minutes, and then the sodium sulfate is filtered. Acrude product obtained after distilling away toluene under reducedpressure is purified through silica gel column chromatography by usingtoluene/ethyl acetate as an eluent, thereby obtaining 42.1 g of I-7a(yield 77%).

To a 500 ml three-neck flask, 41.0 g of I-7a, 43.5 g of methyl3-(4-iodophenyl)propionate, 22.8 g of potassium carbonate, 1.1 g ofcopper sulfate pentahydrate, and 40 ml of n-tridecane are added, andthis mixture is stirred for 20 hours while being heated at 220° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 20 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 47.0 g of I-7b (yield 72%).

To a 3 L three-neck flask, 43.6 g of I-7b and 450 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 4.4 g ofsodium hydroxide in 450 ml of water is added thereto, followed bystirring at 60° C. for 3 hours. Thereafter, the reaction solution isadded dropwise to an aqueous solution of water 1 L/concentratedhydrochloric acid 20 ml, and the precipitated solid is collected bysuction filtration. This solid is added to a 50 ml of mixed solvent ofacetone/water (volume ratio of 40/60) and stirred while being suspended,and then collected by suction filtration, followed by vacuum drying for10 hours, thereby obtaining 31.2 g of I-7c (yield 74%).

To a 500 ml three-neck flask, 29.5 g of I-7c, 11.8 g of4-chloromethylstyrene, 10.6 g of potassium carbonate, 0.17 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 3 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 29.7 g of a charge transport agent (I)-7 of the exemplaryembodiment of the invention (yield 79%).

The IR spectrum of the obtained compound (I)-7 is shown in FIG. 4.

Synthesis Example 1-2

—Synthesis of Charge Transport Agent (I)-15 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 68.3 g of4,4′-bis(2-methoxycarbonylethyl)diphenylamine, 46.4 g of 4-iodoxylene,30.4 g of potassium carbonate, 1.5 g of copper sulfate pentahydrate, and50 ml of n-tridecane are added, and this mixture is stirred for 20 hourswhile being heated at 220° C. under nitrogen flow. Thereafter, thetemperature is reduced to room temperature, and 200 ml of toluene and150 ml of water are added thereto, thereby performing liquid separation.A toluene layer is collected, 20 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away toluene underreduced pressure is purified through silica gel column chromatography byusing toluene/ethyl acetate as an eluent, thereby obtaining 65.1 g ofI-15a (yield 73%).

To a 3 L three-neck flask, 59.4 g of I-15a and 450 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 11.7 g ofsodium hydroxide in 450 ml of water is added thereto, followed bystirring at 60° C. for 3 hours. Thereafter, the reaction solution isadded dropwise to an aqueous solution of water 1 L/concentratedhydrochloric acid 60 ml, and the precipitated solid is collected bysuction filtration. This solid is added to a 50 ml of mixed solvent ofacetone/water (volume ratio of 40/60) and stirred while being suspended,and then collected by suction filtration, followed by vacuum drying for10 hours, thereby obtaining 46.2 g of I-15b (yield 83%).

To a 500 ml three-neck flask, 29.2 g of I-15b, 23.5 g of4-chloromethylstyrene, 21.3 g of potassium carbonate, 0.17 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 3 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 36.4 g of a charge transport agent (I)-15 of the exemplaryembodiment of the invention (yield 80%).

The IR spectrum of the obtained compound (I)-15 is shown in FIG. 5.

Synthesis Example 1-3

—Synthesis of Charge Transport Agent (I)-17 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 68.3 g of4,4′-bis(2-methoxycarbonylethyl)diphenylamine, 56.0 g of 4-iodobiphenyl,30.4 g of potassium carbonate, 1.5 g of copper sulfate pentahydrate, and50 ml of n-tridecane are added, and this mixture is stirred for 20 hourswhile being heated at 220° C. under nitrogen flow. Thereafter, thetemperature is reduced to room temperature, and 200 ml of toluene and150 ml of water are added thereto, thereby performing liquid separation.A toluene layer is collected, 20 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away toluene underreduced pressure is purified through silica gel column chromatography byusing toluene/ethyl acetate as an eluent, thereby obtaining 74.0 g ofI-17a (yield 75%).

To a 3 L three-neck flask, 65.8 g of I-17a and 450 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 11.7 g ofsodium hydroxide in 450 ml of water is added thereto, followed bystirring at 60° C. for 3 hours. Thereafter, the reaction solution isadded dropwise to an aqueous solution of water 1 L/concentratedhydrochloric acid 60 ml, and the precipitated solid is collected bysuction filtration. This solid is added to a 50 ml of mixed solvent ofacetone/water (volume ratio of 40/60) and stirred while being suspended,and then collected by suction filtration, followed by vacuum drying for10 hours, thereby obtaining 53.4 g of I-17b (yield 86%).

To a 500 ml three-neck flask, 32.6 g of I-17b, 23.5 g of4-chloromethylstyrene, 21.3 g of potassium carbonate, 0.17 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 3 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 36.8 g of a charge transport agent (I)-17 of the exemplaryembodiment of the invention (yield 81%).

The IR spectrum of the obtained compound (I)-17 is shown in FIG. 6.

Synthesis Example 1-4

—Synthesis of Charge Transport Agent (I)-23 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 56.7 g of methyl3-[4-(3,4-dimethylphenylamino)phenyl)]propionate, 43.4 g of4,4′-diiodo-3,3′-dimethyl-1,1′-biphenyl, 30.4 g of potassium carbonate,1.5 g of copper sulfate pentahydrate, and 50 ml of n-tridecane areadded, and this mixture is stirred for 20 hours while being heated at220° C. under nitrogen flow. Thereafter, the temperature is reduced toroom temperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 48.4 g of I-23a (yield 65%).

To a 3 L three-neck flask, 37.3 g of I-23a and 350 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 4.4 g ofsodium hydroxide in 350 ml of water is added thereto, and then thismixture is stirred for 5 hours while being heated at 60° C. Thereafter,the reaction solution is added dropwise to an aqueous solution of water1 L/concentrated hydrochloric acid 20 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 32.6 g of I-23b (yield 91%).

To a 500 ml three-neck flask, 25.1 g of I-23b, 11.8 g of4-chloromethylstyrene, 10.6 g of potassium carbonate, 0.09 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 28.2 g of a charge transport agent (I)-23 of the exemplaryembodiment of the invention (yield 85%).

The IR spectrum of the obtained compound (I)-23 is shown in FIG. 7.

Synthesis Example 1-5

—Synthesis of Charge Transport Agent (I)-25 Exemplary Embodiment of theInvention—

To a 500 ml three-neck flask, 51.1 g of methyl3-[4-(phenylamino)phenyl]propionate, 43.4 g of1,2-bis(4-iodophenyl)ethane, 30.4 g of potassium carbonate, 1.5 g ofcopper sulfate pentahydrate, and 50 ml of n-tridecane are added, andthis mixture is stirred for 20 hours while being heated at 220° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 51.7 g of I-25a (yield 75%).

To a 3 L three-neck flask, 34.4 g of I-25a and 350 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 4.4 g ofsodium hydroxide in 350 ml of water is added thereto, and then thismixture is stirred for 5 hours while being heated at 60° C. Thereafter,the reaction solution is added dropwise to an aqueous solution of water1 L/concentrated hydrochloric acid 20 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 28.4 g of I-25b (yield 86%).

To a 500 ml three-neck flask, 23.1 g of I-25b, 11.8 g of4-chloromethylstyrene, 10.6 g of potassium carbonate, 0.09 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 25.6 g of a charge transport agent (I)-25 of the exemplaryembodiment of the invention (yield 82%).

The IR spectrum of the obtained compound (I)-25 is shown in FIG. 8.

Synthesis Example 1-6

—Synthesis of Charge Transport Agent (I)-27 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 56.7 g of methyl3-[4-(3,4-dimethylphenylamino)phenyl]propionate, 43.4 g of1,2-bis(4-iodophenyl)ethane, 30.4 g of potassium carbonate, 1.5 g ofcopper sulfate pentahydrate, and 50 ml of n-tridecane are added, andthis mixture is stirred for 20 hours while being heated at 220° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 54.4 g of I-27a (yield 73%).

To a 3 L three-neck flask, 37.3 g of I-27a and 350 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 4.4 g ofsodium hydroxide in 350 ml of water is added thereto, and then thismixture is stirred for 5 hours while being heated at 60° C. Thereafter,the reaction solution is added dropwise to an aqueous solution of water1 L/concentrated hydrochloric acid 20 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 29.4 g of I-27b (yield 82%).

To a 500 ml three-neck flask, 25.1 g of I-27b, 11.8 g of4-chloromethylstyrene, 10.6 g of potassium carbonate, 0.09 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 26.2 g of a charge transport agent (I)-27 of the exemplaryembodiment of the invention (yield 79%).

The IR spectrum of the obtained compound (I)-27 is shown in FIG. 9.

Synthesis Example 1-7

—Synthesis of Charge Transport Agent (I)-30 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 66.3 g of methyl3-[4-(4-phenyl)phenylaminophenyl]propionate, 43.4 g of1,2-bis(4-iodophenyl)ethane, 30.4 g of potassium carbonate, 1.5 g ofcopper sulfate pentahydrate, and 50 ml of n-tridecane are added, andthis mixture is stirred for 20 hours while being heated at 220° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 62.2 g of I-30a (yield 74%).

To a 3 L three-neck flask, 42.1 g of I-30a and 350 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 4.4 g ofsodium hydroxide in 350 ml of water is added thereto, and this mixtureis stirred for hours while being heated at 60° C. Thereafter, thereaction solution is added dropwise to an aqueous solution of water 1L/concentrated hydrochloric acid 20 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 34.1 g of I-30b (yield 84%).

To a 500 ml three-neck flask, 28.5 g of I-30b, 11.8 g of4-chloromethylstyrene, 10.6 g of potassium carbonate, 0.09 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 26.7 g of a charge transport agent (I)-30 of the exemplaryembodiment of the invention (yield 73%).

The IR spectrum of the obtained compound (I)-30 is shown in FIG. 10.

Synthesis Example 1-8

—Synthesis of Charge Transport Agent (I)-43 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 68.3 g of4,4′-bis(2-methoxycarbonylethyl)diphenylamine, 43.4 g of4,4′-diiodo-3,3′-dimethyl-1,1′-biphenyl, 30.4 g of potassium carbonate,1.5 g of copper sulfate pentahydrate, and 50 ml of n-tridecane areadded, and this mixture is stirred for 20 hours while being heated at220° C. under nitrogen flow. Thereafter, the temperature is reduced toroom temperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 56.0 g of I-43a (yield 65%).

To a 3 L three-neck flask, 43.1 g of I-43a and 350 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 8.8 g ofsodium hydroxide in 350 ml of water is added thereto, and this mixtureis stirred for hours while being heated at 60° C. Thereafter, thereaction solution is added dropwise to an aqueous solution of water 1L/concentrated hydrochloric acid 40 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 36.6 g of I-43b (yield 91%).

To a 500 ml three-neck flask, 28.2 g of I-43b, 23.5 g of4-chloromethylstyrene, 21.3 g of potassium carbonate, 0.09 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 37.8 g of a charge transport agent (I)-43 of the exemplaryembodiment of the invention (yield 85%).

The IR spectrum of the obtained compound (I)-43 is shown in FIG. 11.

Synthesis Example 1-9

—Synthesis of Charge Transport Agent (I)-46 of Exemplary Embodiment ofthe Invention—

To a 3 L three-neck flask, 43.1 g of I-43a and 300 ml of tetrahydrofuranare added, followed by stirring. The reaction system is substituted withnitrogen, and then 16.3 g of sodium borohydride is added thereto.Thereafter, 50 ml of methanol is added dropwise thereto over 2 hoursunder heating and refluxing. After the mixture is heated and refluxedfor another 2 hours, the temperature is temporarily cooled to 0° C., 300ml of 2N hydrochloric acid is added dropwise thereto over an hour, andthe temperature is slowly increased to room temperature again.Subsequently, liquid separation is performed by adding 400 ml of ethylacetate, and an ethyl acetate layer is collected. 10 g of sodium sulfateis added thereto, followed by stirring for 10 minutes, and then thesodium sulfate is filtered. A crude product obtained after distillingaway ethyl acetate under reduced pressure is purified through silica gelcolumn chromatography by using toluene/ethyl acetate as an eluent,thereby obtaining 28.5 g of I-46a (yield 76%).

To a 500 ml three-neck flask, 26.2 g of I-46a, 14.9 g of succinicanhydride, and 70 ml of tetrahydrofuran are added. While this mixture isstirred under nitrogen flow, 14.9 g of triethylamine and 0.2 g ofN,N-dimethylaminopyridine are added thereto, followed by stirring foranother 2 hours. Thereafter, 200 ml of 1N hydrochloric acid and 300 mlof ethyl acetate are added thereto, thereby performing liquidseparation. An ethyl acetate layer is collected, 10 g of sodium sulfateis added thereto, followed by stirring for 10 minutes, and then thesodium sulfate is filtered. A crude product obtained after distillingaway the ethyl acetate under reduced pressure is purified through silicagel column chromatography by using toluene/ethyl acetate as an eluent,thereby obtaining 35.0 g of I-46b (yield 87%).

To a 500 ml three-neck flask, 23.0 g of I-46b, 13.4 g of4-chloromethylstyrene, 12.2 g of potassium carbonate, 0.05 g ofnitrobenzene, and 100 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 26.1 g of a charge transport agent (I)-46 of the exemplaryembodiment of the invention (yield 81%).

The IR spectrum of the obtained compound (I)-46 is shown in FIG. 12.

Synthesis Example 1-10

—Synthesis of Charge Transport Agent (I)-53 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 68.3 g of4,4′-bis(2-methoxycarbonylethyl)diphenylamine, 43.4 g of1,2-bis(4-iodophenyl)ethane, 30.4 g of potassium carbonate, 1.5 g ofcopper sulfate pentahydrate, and 50 ml of n-tridecane are added, andthis mixture is stirred for 20 hours while being heated at 220° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 59.4 g of I-53a (yield 69%).

To a 3 L three-neck flask, 43.1 g of I-53a and 350 ml of tetrahydrofuranare added, and an aqueous solution obtained by dissolving 8.8 g ofsodium hydroxide in 350 ml of water is added thereto, and this mixtureis stirred for hours while being heated at 60° C. Thereafter, thereaction solution is added dropwise to an aqueous solution of water 1L/concentrated hydrochloric acid 40 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 34.2 g of I-53b (yield 85%).

To a 500 ml three-neck flask, 28.2 g of I-53b, 23.5 g of4-chloromethylstyrene, 21.3 g of potassium carbonate, 0.09 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 35.1 g of a charge transport agent (I)-53 of the exemplaryembodiment of the invention (yield 79%).

The IR spectrum of the obtained compound (I)-53 is shown in FIG. 13.

Example 1-1

—Preparation of Charge Transporting Film—

A coating liquid for forming a charge transporting film having thefollowing composition is prepared.

(Charge Transport Agent)

The charge transport material ((I)-15) synthesized in the SynthesizeExample 1-1: 100 parts by weight

(Initiator)

V-601 (manufactured by Wako Pure Chemical Industries, Ltd.): 2 parts byweight

(Solvent)

Mixed solvent of tetrahydrofuran (THF)/toluene (volume ratio of 40/60):150 parts by weight

An ITO glass substrate that includes an ITO film on a glass substrate isprepared, and the ITO film is etched into an approximately strip shapehaving a width of 2 mm, thereby forming an ITO electrode (anode). ThisITO glass substrate is subjected to ultrasonic cleaning by usingisopropanol (used in the field of electronic industry, manufactured byKanto Chemical Co., Inc.) and then dried using a spin coater.

In the ITO glass substrate, the coating liquid for forming a chargetransporting film is coated onto the surface where the ITO electrode hasbeen formed, and the resultant is heated at 150° C. for 40 minutes in anatmosphere in which an oxygen concentration of about 100 ppm, therebyforming a 5 μm charge transporting film 1-1.

(Measurement of Mobility Stability)

30 V/μm of an electric field is created for the charge transporting filmby using TOF-401 (manufactured by Sumitomo Heavy Industries, Ltd.), andmobility is repeatedly measured 100 times, and the mobility stability isevaluated from the following formula.

“∥” indicates an absolute value, and A++ indicates the bestcharacteristic.

Mobility stability=|(mobility measured firstly)−(mobility measured bythe 100^(th) measurement)/(mobility measured firstly)

A++: less than 0.05

A+: 0.05 or more and less than 0.08

A: 0.08 or more and less than 0.1

B: 0.1 or more and less than 0.2

C: 0.2 or more

—Preparation of Organic Electroluminescence Element—

An ITO glass substrate that includes an ITO film on a glass substrate isprepared, and the ITO film is etched into an approximately strip shapehaving a width of 2 mm, thereby forming an ITO electrode (anode). ThisITO glass substrate is subjected to ultrasonic cleaning by usingisopropanol (used in the field of electronic industry, manufactured byKanto Chemical Co., Inc.) and then dried using a spin coater.

Thereafter, in the ITO glass substrate, copper phthalocyanine preparedby sublimation is vacuum-deposited onto the surface where the ITOelectrode is formed, thereby forming a thin film having a thickness of0.015 μm.

The coating liquid for forming a charge transporting film is coated ontothe copper phthalocyanine film, followed by heating at 145° C. for 40minutes in an atmosphere in which an oxygen concentration of about 100ppm, thereby forming a 0.05 μm thin film. In this manner, a holetransporting layer having a double-layer structure is formed on the ITOelectrode.

Subsequently, on the hole transporting layer,tris(8-hydroxyquinoline)aluminum (Alq) is vapor-deposited as a luminousmaterial, thereby forming a luminous layer having a thickness of 0.060μm.

In addition, on the luminous layer, a Mg—Ag alloy is vapor-deposited bycodeposition, thereby forming a Mg—Ag electrode (cathode) with anapproximately strip shape having a width of 2 mm and a thickness of 0.13μm. In this manner, an organic electroluminescence element 1-1 isobtained. The ITO electrode and Mg—Ag electrode are formed such thatthese electrodes extend at right angles to each other. An effective areaof the obtained organic electroluminescence element 1-1 is 0.04 cm².

Comparative Example 1-1

A comparative charge transporting film 1-1 and a comparative organicelectroluminescence element 1-1 are obtained in the same manner as thatin Example 1-1, except that the charge transport material (I-15) ischanged to a comparative compound (AC-1) having the following structure.The resultant is taken as the comparative electroluminescence element1-1.

Comparative Example 1-2

A comparative charge transporting film 1-2 and a comparative organicelectroluminescence element 1-2 are obtained in the same manner as thatin Example 1-1, except that the charge transport material (I-15) ischanged to a comparative compound (AC-2) having the following structure.The resultant is taken as the comparative electroluminescence element1-2.

Examples 1-2 to 1-16

Charge transporting films 1-2 to 1-16 and organic electroluminescenceelements 1-2 to 1-16 are obtained in the same manner as that in Example1-1, except that the charge transport material, the initiator, and thesolvent in Example 1-1 are changed to those described in Table 7.

(Element Characteristic Evaluation)

The characteristics of the organic electroluminescence elements obtainedin examples and comparative examples are evaluated in the followingmanner.

<Maximum Luminance>

In vacuum (0.125 Pa), the ITO electrode is used as a positive electrode(anode), and the MG-Ag electrode is used as a negative electrode(cathode). DC voltage is applied to these electrodes so as to cause theelectrodes to emit light, and the maximum luminance at this time isevaluated. The results are shown in Table 7.

The evaluation criteria of the maximum luminance are as follows (theunit of numerical values is cd/m²), and A++ indicates the bestcharacteristic.

A++: 800 or more

A+: 750 or more and less than 800

A: 700 or more and less than 750

B: 650 or more and less than 700

C: less than 650

<Element Lifetime>

The emission lifetime of the organic electroluminescence element in drynitrogen is measured in the following manner.

The element life time is evaluated by using a relative time obtainedwhen the initial luminance in a DC driving mode at room temperature isset to 500 cd/m², and a driving time at a point of time when theluminance (initial luminance L0: 500 cd/m²) of the element ofComparative Example 1-1 becomes (luminance L/initial luminance L0)=0.5is set to 1.0, and using voltage rise amount (=voltage/initial drivingvoltage) at a point of time when the luminance of the element becomes(luminance L/initial luminance L0)=0.5.

The evaluation criteria of the relative time (L/L0=0.5) and the voltagerise (at the time when L/L0=0.5) are as follows.

Relative Time (L/L0=0.5)

A++ indicates the best characteristic.

A++: 1.6 or more

A+: 1.4 or more and less than 1.6

A: 1.2 or more and less than 1.4

B: 1.0 or more and less than 1.2

C: less than 1.0

Voltage Rise (at the Time when L/L0=0.5)

A++ indicates the best characteristic.

A++: 1.0 or more and less than 1.1

A+: 1.1 or more and less than 1.2

A: 1.2 or more and less than 1.3

B: 1.3 or more and less than 1.4

C: 1.4 or more

TABLE 7 Characteristics Novel reactive of charge Characteristics oforganic compound of the transporting electroluminescence elementexemplary film Voltage Relative embodiment of the Solvent NumericalMobility Maximum rise time invention Initiator Weight ratio in ( )stability luminance (@L/L0 = 0.5) (L/L0 = 0.5) Example 1 I-15 V-601THF/toluene (40/60) A A A A Comparative AC-1 V-601 THF/toluene (40/60) BB B A Example 1 Comparative AC-2 V-601 THF/toluene (40/60) C C B CExample 2 Example 2 I-17 V-601 THF/toluene (40/60) A A A A Example 3I-23 V-601 THF/toluene (40/60) A+ A+ A A Example 4 I-25 V-601THF/toluene (40/60) A A A A Example 5 I-27 V-601 THF/toluene (40/60) A+A+ A A Example 6 I-30 V-601 THF/toluene (40/60) A+ A+ A A Example 7 I-43V-601 THF/toluene (40/60) A++ A+ A+ A+ Example 8 I-46 V-601 THF/toluene(40/60) A+ A A A+ Example 9 I-53 V-601 THF/toluene (40/60) A++ A+ A+ A+Example 10 I-43/I-61 V-601 THF/toluene (40/60) A++ A+ A+ A+ (Weightratio 95/5) Example 11 I-15 VE-073 THF/toluene (50/50) A A A A Example12 I-43 OTazo THF/toluene (40/60) A++ A+ A+ A+ Example 13 I-17 V-601n-butyl acetate A A A A Example 14 I-53 V-601 Methyl i-butyl ketone A++A+ A+ A+ Example 15 I-53/I-7 V-601 THF/toluene (20/80) A++ A+ A+ A+(Weight ratio 75/25) Example 16 I-43/I-7 V-601 THF/toluene (30/70) A++A+ A+ A+ (Weight ratio 70/30)

VE-073: polymerization initiator (manufactured by Wako Pure ChemicalIndustries, Ltd.)

OTazo-15: polymerization initiator (manufactured by Otsuka Chemical Co.,Ltd.)

Synthesis Example 2-1

—Synthesis of Charge Transport Agent (I′)-15 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 68.3 g of4,4′-bis(2-methoxycarbonylethyl)diphenylamine, 46.4 g of 4-iodoxylene,30.4 g of potassium carbonate, 1.5 g of copper sulfate pentahydrate, and50 ml of n-tridecane are added, and this mixture is stirred for 20 hourswhile being heated at 220° C. under nitrogen flow. Thereafter, thetemperature is reduced to room temperature, and 200 ml of toluene and150 ml of water are added thereto, thereby performing liquid separation.A toluene layer is collected, 20 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away toluene underreduced pressure is purified through silica gel column chromatography byusing toluene/ethyl acetate as an eluent, thereby obtaining 65.1 g ofI′-15a (yield 73%).

To a 3 L three-neck flask, 59.4 g of I′-15a and 450 ml oftetrahydrofuran are added, and an aqueous solution obtained bydissolving 11.7 g of sodium hydroxide in 450 ml of water is addedthereto, followed by stirring at 60° C. for 3 hours. Thereafter, thereaction solution is added dropwise to an aqueous solution of water 1L/concentrated hydrochloric acid 60 ml, and the precipitated solid iscollected by suction filtration. This solid is added to a 50 ml of mixedsolvent of acetone/water (volume ratio of 40/60) and stirred while beingsuspended, and then collected by suction filtration, followed by vacuumdrying for 10 hours, thereby obtaining 46.2 g of I′-15b (yield 83%).

To a 500 ml three-neck flask, 29.2 g of I′-15b, 23.5 g of4-chloromethylstyrene, 21.3 g of potassium carbonate, 0.17 g ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 3 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 36.4 g of a charge transport agent (I′)-15 of the exemplaryembodiment of the invention (yield 80%).

The IR spectrum of the obtained compound (I′)-15 is shown in FIG. 17.

Synthesis Example 2-2

—Synthesis of Charge Transport Agent (I′)-43 of Exemplary Embodiment ofthe Invention—

To a 500 ml three-neck flask, 68.3 g of4,4′-bis(2-methoxycarbonylethyl)diphenylamine, 43.4 g of4,4′-diiodo-3,3′-dimethyl-1,1′-biphenyl, 30.4 g of potassium carbonate,1.5 g of copper sulfate pentahydrate, and 50 ml of n-tridecane areadded, and this mixture is stirred for 20 hours while being heated at220° C. under nitrogen flow. Thereafter, the temperature is reduced toroom temperature, and 200 ml of toluene and 150 ml of water are addedthereto, thereby performing liquid separation. A toluene layer iscollected, 10 g of sodium sulfate is added thereto, followed by stirringfor 10 minutes, and then the sodium sulfate is filtered. A crude productobtained after distilling away toluene under reduced pressure ispurified through silica gel column chromatography by using toluene/ethylacetate as an eluent, thereby obtaining 56.0 g of I′-43a (yield 65%).

To a 3 L three-neck flask, 43.1 g of I′-43a and 350 ml oftetrahydrofuran are added, and an aqueous solution obtained bydissolving 8.8 g of sodium hydroxide in 350 ml of water is addedthereto, and this mixture is stirred for hours while being heated at 60°C. Thereafter, the reaction solution is added dropwise to an aqueoussolution of water 1 L/concentrated hydrochloric acid 40 ml, and theprecipitated solid is collected by suction filtration. This solid isadded to a 50 ml of mixed solvent of acetone/water (volume ratio of40/60) and stirred while being suspended, and then collected by suctionfiltration, followed by vacuum drying for 10 hours, thereby obtaining36.6 g of I′-43b (yield 91%).

To a 500 ml three-neck flask, 28.2 g of I′-43b, 23.5 g of4-chloromethylstyrene, 21.3 g of potassium carbonate, 0.09 q ofnitrobenzene, and 175 ml of DMF (N,N-dimethylformamide) are added, andthis mixture is stirred for 5 hours while being heated at 75° C. undernitrogen flow. Thereafter, the temperature is reduced to roomtemperature, and ethyl acetate 200 ml/water 200 ml are added to thereaction solution, thereby performing liquid separation. An ethylacetate layer is collected, 10 g of sodium sulfate is added thereto,followed by stirring for 10 minutes, and then the sodium sulfate isfiltered. A crude product obtained after distilling away the ethylacetate under reduced pressure is purified through silica gel columnchromatography by using toluene/ethyl acetate as an eluent, therebyobtaining 37.8 g of a charge transport agent (I′)-43 of the exemplaryembodiment of the invention (yield 85%).

The IR spectrum of the obtained compound (I′)-43 is shown in FIG. 18.

Example 2-1

(Preparation of Electrophotographic Photoreceptor)

—Preparation of Undercoat Layer 4—

100 parts by weight of zinc oxide (average particle size of 70 nm:manufactured by TAYCA: specific surface area of 15 m²/g) is mixed with500 parts by weight of toluene under stirring, and 1.3 part by weight ofa silane coupling agent (KEB503: manufactured by Shin-Etsu Chemical Co.,Ltd.) is added thereto, followed by stirring for 2 hours. Thereafter,toluene is distilled away through distillation under reduced pressure,and the resultant is baked at 120° C. for 3 hours, thereby obtainingzinc oxide surface-treated with the silane coupling agent. 110 parts byweight of the surface-treated zinc oxide is mixed with 500 parts byweight of tetrahydrofuran under stirring, and a solution obtained bydissolving 0.6 parts by weight of alizarin in 50 parts by weight oftetrahydrofuran is added thereto, followed by stirring at 50° C. for 5hours. Thereafter, the alizarin-imparted zinc oxide is filtered byfiltration under reduced pressure, followed by drying at 60° C. underreduced pressure, thereby obtaining alizarin-imparted zinc oxide.

38 parts by weight of a solution obtained by mixing 60 parts by weightof the alizarin-imparted zinc oxide, 13.5 parts by weight of a curingagent (blocked isocyanate Sumidur BL 3175, manufactured by Sumika BayerUrethane Co., Ltd.), and 15 parts by weight of a butyral resin (S-LECBM-1, manufactured by Sekisui Chemical Co., Ltd.) with 85 parts byweight of methyl ethyl ketone is mixed with 25 parts by weight of methylethyl ketone, and the resultant is dispersed with a sand mill for 2hours by using glass beads having a diameter of 1 mmφ, thereby obtaininga dispersion.

To the obtained dispersion, 0.005 parts by weight of dioctyltindilaurate and 40 parts by weight of silicone resin particles (Tospearl145, manufactured by GE Toshiba Silicones, Co., Ltd.) are added as acatalyst, thereby obtaining a coating liquid for forming an undercoatlayer. This coating liquid is coated onto an aluminum substrate by dipcoating, followed by drying and curing at 170° C. for 40 minutes,thereby obtaining an undercoat layer having a thickness of 20 μm.

—Preparation of Charge Generating Layer 2A—

A mixture including 15 parts by weight of hydroxy gallium phthalocyanine(CGM-1) as a charge generating material in which the Bragg angle(2θ±0.2°) of an X-ray diffraction spectrum using X-rays having Cukαcharacteristics has diffraction peaks at positions of at least 7.3°,16.0°, 24.9°, and 28.0°, 10 parts by weight of a vinyl chloride-vinylacetate copolymer resin (VMCH, manufactured by Nippon Unicar Co., Ltd.)as a binder resin, and 200 parts by weight of n-butyl acetate isdispersed with a sand mill for 4 hours by using glass beads having adiameter of 1 mmφ. To the obtained dispersion, 175 parts by weight ofn-butyl acetate and 180 parts by weight of methyl ethyl ketone areadded, followed by stirring, thereby obtaining a coating liquid forforming a charge generating layer. This coating liquid for forming acharge generating layer is coated onto the undercoat layer bydip-coating, followed by drying at room temperature (25° C.), therebyforming a charge generating layer having a film thickness of 0.2 μm.

—Preparation of Charge Transporting Layer 2B-1—

A coating liquid for forming the charge transporting layer 2B-1 havingthe following composition is prepared.

(Charge Transport Agent)

N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′]biphenyl-4,4′-diamine(CTM-1): 45 parts by weight

(Resin)

Bisphenol Z polycarbonate resin (written as “PCZ 500” hereinafter,viscosity average molecular weight: 50000): 55 parts by weight

(Solvent)

Chlorobenzene: 800 parts by weight

This coating liquid is coated onto the charge generating layer, followedby drying at 130° C. for 45 minutes, thereby obtaining the chargetransporting layer 2B-1 having a film thickness of 20 μm.

—Preparation of Charge Transporting Layer 2B-2—

A coating liquid for forming the charge transporting layer 2B-2 havingthe following composition is prepared.

(Charge Transport Agent)

Charge transport material ((I′)-15) synthesized in the Synthesis Example2-1: 100 parts by weight

(Initiator)

V-601 (manufactured by Wako Pure Chemical Industries, Ltd.): 2 parts byweight

(Solvent)

Mixed solvent of tetrahydrofuran (THF)/toluene (weight ratio of 60/40):150 parts by weight

This coating liquid is coated onto the charge transporting layer 2B-1,followed by heating at 150° C. for minutes in an atmosphere in which anoxygen concentration is about 100 ppm, thereby forming a 7 μm protectivelayer.

In the manner described above, an electrophotographic photoreceptor isobtained, and this photoreceptor is taken as a photoreceptor 2-1.

Examples 2-2 to 2-22 and Comparative Examples 2-1 and 2-2

(Preparation of Electrophotographic Photoreceptor)

Electrophotographic photoreceptors are obtained in the same manner asthat in Example 2-1, except that the charge transport material in thecoating liquid for forming the charge transporting layer 2B-2 in Example2-1 is changed as shown in Table 8. These photoreceptors are taken asphotoreceptors 2-2 to 2-22 and comparative photoreceptors 2-1 and 2-2.

[Photoreceptor Running Evaluation 1]

The electrophotographic photoreceptors prepared in the Examples 2-1 to2-22 and Comparative Examples 2-1 and 2-2 are mounted on a DocuCentreColor 400CP (manufactured by Fuji Xerox Co., Ltd.), and the pattern forimage evaluation shown in FIG. 16A is output in normal environment (20°C., 50% RH). Thereafter, 30000 sheets of black solid pattern areconsecutively output, and then the pattern for image evaluation isoutput again. In addition, the amount of light is adjusted according tothe sensitivity of the charge generating material by using a filter.

<Image Stability>

The patterns for image evaluation output before and after the runningevaluation 1 are compared with each other. The degree of imagedeterioration is visually observed and evaluated in the followingmanner. A++ indicates the best characteristic.

A++: best (deterioration is almost not observed in entire output imagepattern)

A+: in a portion of plural output image patterns, enlarged images showchange.

A: fair (change is not visually confirmed, but enlarged images showchange)

B: though image quality deterioration is confirmed, this is an allowablelevel.

C: image quality deterioration is confirmed, and this is a problematiclevel.

<Electrical Characteristic Stability>

Before and after the photoreceptor running evaluation 1, the respectivephotoreceptors are charged negatively by a scorotron charging devicehaving a grid applied voltage −700 V in normal environment (20° C., 50%RH). Thereafter, the charged photoreceptors are subjected to flashexposure by using a 780 nm semiconductor laser with a light amount of 10mJ/m². After the exposure, a potential (V) of the photoreceptor surfaceafter 10 seconds is measured, and the value is taken as the value of aresidual potential. All of the photoreceptors show negative residualpotential value. Regarding the respective photoreceptors, a value of(residual potential before running evaluation 1)−(residual potentialafter running evaluation 1) is calculated, thereby evaluating theelectrical characteristic stability. A++ indicates the bestcharacteristic.

A++: less than 10 V

A+: 10 V or more and less than 20 V

A: 20 V or more and less than 30 V

B: 30 V or more and less than 50 V

C: 50 V or more

<Mechanical Strength>

The degree of scratches caused on the photoreceptor surface after thephotoreceptor evaluation 1 is judged by visual observation. A+ indicatesthe best characteristic.

A+: scratches are not confirmed even in microscopic observation.

A: though not confirmed visually, small scratches are confirmed inmicroscopic observation.

B: scratches are partially caused.

C: scratches are caused in the entire photoreceptor surface.

[Photoreceptor Running Evaluation 2]

The electrophotographic photoreceptors prepared in the Examples 2-1 to2-22 and Comparative Examples 2-1 and 2-2 are mounted on a DocuCentreColor 400CP (manufactured by Fuji Xerox Co., Ltd.). First, the patternfor image evaluation shown in FIG. 16A is output at a low temperatureand low humidity (20° C., 30% RH) and taken as an [evaluation image 1].Subsequently, 10000 sheets of black solid patterns are consecutivelyoutput, and then the pattern for image evaluation is output and taken asan [evaluation image 2]. The photoreceptor is left as it is for 24 hoursin a low temperature and low humidity (20° C., 30% RH) environment, andthen the pattern for image evaluation is output and taken as an[evaluation image 3]. Thereafter, 5000 sheets of black solid patternsare output in a high temperature and high humidity (28° C., 60% RH)environment, and then the pattern for image evaluation is output andtaken as an [evaluation image 4]. The photoreceptor is left as it is for24 hours in a high temperature and high humidity (28° C., 60% RH)environment, and then the pattern for image evaluation is output andtaken as an [evaluation image 5]. The photoreceptor is returned to a lowtemperature and low humidity (20° C., 30% RH) environment, 20000 sheetsof black solid patterns are output again, and the pattern for imageevaluation is output and taken as an [evaluation image 6].

<Ghost Evaluation>

The [evaluation image 3] and [evaluation image 5] are compared with the[evaluation image 2] and [evaluation image 4] respectively, and thedegree of image quality deterioration is evaluated by visualobservation. A++ indicates the best characteristic.

A+: as excellent as FIG. 16A

A: though image quality is as excellent as FIG. 16A, ghost occursslightly.

B: ghost is slightly noticeable as FIG. 16B.

C: ghost is clearly confirmed as FIG. 16C.

TABLE 8 Charge transporting layer 2B-2 Charge transport material (A) ofexemplary Evaluation result embodiment Electrical of the Imagecharacter- Mechanical invention stability istics strength Ghost Example2-1 I′-15 A A A A Comparative AC-1 B B B A Example 2-1 Comparative AC-2C C B C Example 2-2 Example 2-2 I′-17 A A A A Example 2-3 I′-23 A A A AExample 2-4 I′-27 A A A A Example 2-5 I′-30 A A A A Example 2-6 I′-32 AA A+ A Example 2-7 I′-34 A+ A A+ A Example 2-8 I′-36 A A+ A A Example2-9 I′-43 A++ A+ A+ A+ Example 2-10 I′-46 A++ A+ A A+ Example 2-11 I′-53A++ A+ A+ A+ Example 2-12 I′-48 A++ A+ A+ A+ Example 2-13 I′-40 A++ A+A+ A+ Example 2-14 I′-58 A A+ A+ A Example 2-15 I′-122 A+ A+ A A+Example 2-16 I′-123 A+ A A+ A Example 2-17 I′-124 A A A A Example 2-18I′-125 A A A A Example 2-19 I′-126 A A A A Example 2-20 I′-127 A A A AExample 2-21 I′-43/1′-121 A++ A+ A+ A+ (Weight ratio 95/5) Example 2-22I-43/I-121 A++ A+ A+ A+ (Weight ratio 50/50)

Examples 2-23 to 2-37

(Preparation of Electrophotographic Photoreceptor)

Electrophotographic photoreceptors are obtained in the same manner asthat in Example 2-1, except that the charge generating material incharge generating layer 2A, the charge transport agent in chargetransporting layer 2B-1, the respective components of the chargetransporting layer 2B-2, and types of solvents in Example 2-1 arechanged as shown in Table 9. These photoreceptors are taken asphotoreceptors 2-23 to 2-37.

The photoreceptors 2-23 to 2-37 are evaluated in the same manner as thatin Example 2-1, and the results are shown in Table 9. In addition, thecompounds in the table are as follows.

CGM-2: titanyl phthalocyanine

CTM-2: the following compound

CTM-3: the following compound

Monomer-1: A-DCP (bifunctional acrylate monomer manufactured byShin-Nakamura Chemicals Co., Ltd.)

Monomer-2: A-DPH (hexafunctional acrylate monomer manufactured byShin-Nakamura Chemicals Co., Ltd.)

Monomer-3: BPE-200 (bifunctional methacrylate monomer manufactured byShin-Nakamura Chemicals Co., Ltd.)

(Initiator)

V-40: initiator manufactured by Wako Pure Chemical Industries, Ltd.(thermal radical generator)

VE-073: initiator manufactured by Wako Pure Chemical Industries, Ltd.(thermal radical generator)

OTazo-15: initiator manufactured by Otsuka Chemical Co., Ltd. (thermalradical generator)

Perhexyl O: initiator manufactured by Nof Corporation (thermal radicalgenerator)

(Resin)

S-LEC B BX-L: polyvinyl butyral resin manufactured by Sekisui ChemicalCo., Ltd.

TABLE 9 Charge transporting layer 2B-2 Charge Charge transportingtransport Charge layer 2B-1 material Radical- generating Charge (A) ofCharge polymerizable layer 2A transport exemplary transport monomer notCharge material embodiment material having charge generating Weightratio of the other than transport material in ( ) invention Initiator(A) function Example 2-23 CGM-1 CTM-1 I′-27 VE-073 None None Example2-24 CGM-1 CTM-1 I′-53 V-40 None None Example 2-25 CGM-1 CTM-1 I′-43OTazo-15 None None Example 2-26 CGM-1 CTM-1 I′-40 Perhexyl O None NoneExample 2-27 CGM-1 CTM-1 I′-15 V-601 None None Example 2-27 CGM-1 CTM-1I′-53 V-601 None None Example 2-28 CGM-1 CTM-1 I′-43 V-601 None NoneExample 2-29 CGM-1 CTM-1 I′-53 V-601 None None Example 2-30 CGM-1 CTM-1I′-23 V-601 CTM-2 None (15 parts by weight) Example 2-31 CGM-1 CTM-1I′-46 V-601 CTM-3 None (20 parts by weight) Example 2-32 CGM-1 CTM-1I′-15 V-601 None Monomer-1 (10 parts by weight) Example 2-33 CGM-1 CTM-1I′-30 V-601 None Monomer-2 (5 parts by weight) Example 2-34 CGM-1 CTM-1I′-53 V-601 None Monomer-3 (10 parts by weight) Example 2-35 CGM-1 CTM-2I′-15 V-601 None None Example 2-36 CGM-1 CTM-1/CTM-3 I′-43 V-601 NoneNone (70/30) Example 2-37 CGM-2 CTM-1 I′-53 V-601 None None Chargetransporting layer 2B-2 Evaluation result Coating solvent ImageElectrical Mechanical Resin Weight ratio in ( ) stability characteristicstrength Ghost Example 2-23 None THF/toluene (60/40) A A A A Example2-24 None THF/toluene (60/40) A++ A+ A+ A+ Example 2-25 None THF/toluene(60/40) A++ A+ A+ A+ Example 2-26 None THF/toluene (60/40) A++ A+ A+ A+Example 2-27 PCZ500 THF/toluene (60/40) A A A A Example 2-27 BX-LTHF/toluene (60/40) A++ A+ A+ A+ Example 2-28 None n-butyl acetate A++A+ A+ A+ xample 2-29 None Methyl i-butyl A++ A+ A+ A+ ketone Example2-30 None THF/toluene (60/40) A A A A Example 2-31 None THF/toluene(60/40) A++ A+ A A+ Example 2-32 None THF/toluene (60/40) A A A AExample 2-33 None THF/toluene (60/40) A A A A Example 2-34 NoneTHF/toluene (60/40) A++ A+ A+ A+ Example 2-35 None THF/toluene (60/40) AA A A Example 2-36 None THF/toluene (60/40) A++ A+ A+ A+ Example 2-37None THF/toluene (60/40) A++ A+ A+ A+

The foregoing description of the exemplary embodiments of the presentinvention has been provided for the purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise forms disclosed. Obviously, many modificationsand variations will be apparent to practitioners skilled in the art. Theembodiments were chosen and described in order to best explain theprinciples of the invention and its practical applications, therebyenabling others skilled in the art to understand the invention forvarious embodiments and with the various modifications as are suited tothe particular use contemplated. It is intended that the scope of theinvention be defined by the following claims and their equivalents.

What is claimed is:
 1. An electrophotographic photoreceptor comprisingat least: a conductive substrate; and a photosensitive layer provided onthe conductive substrate, wherein an uppermost surface layer thereof isa layer including a polymerized or cured film of a composition thatcontains one or more kinds of charge transport materials (A2)represented by the following General Formula (I′):

wherein in General Formula (I′), F represents a charge transportingskeleton, D′ represents a group represented by the following GeneralFormula (III′), and m represents an integer of from 1 to 8:

wherein in General Formula (III′), L2 represents a divalent linkinggroup including one or more groups selected from a group consisting of—C(═O)—, —N(R)—, —S—, or a group formed by combining —C(═O)— with —O—,—N(R)—, or —S—, and R represents a hydrogen atom, an alkyl group, anaryl group, or an aralkyl group.
 2. The electrophotographicphotoreceptor according to claim 1, wherein the charge transportmaterial (A2) represented by General Formula (I′) is a charge transportmaterial represented by the following General Formula (II′):

wherein in General Formula (II′), each of Ar¹ to Ar⁴ independentlyrepresents a substituted or unsubstituted aryl group, Ar⁵ represents asubstituted or unsubstituted aryl group or a substituted orunsubstituted arylene group, D has the same definition as that of D inGeneral Formula (I′), each of c1 to c5 represents an integer of from 0to 2, and the sum of c1 to c5 is an integer of from 1 to 8, and k is 0or
 1. 3. The electrophotographic photoreceptor according to claim 1,wherein L2 in General Formula (III′) is a divalent linking groupincluding —C(═O)—O—.
 4. The electrophotographic photoreceptor accordingto claim 1, wherein General Formula (III′) is a compound represented bythe following General Formula (IV):

wherein in General Formula (IV), p represents an integer of from 0 to 4.5. The electrophotographic photoreceptor according to claim 1, wherein min General Formula (I′) is an integer of from 2 to
 6. 6. Theelectrophotographic photoreceptor according to claim 5, wherein m inGeneral Formula (I′) is an integer of from 3 to
 6. 7. Theelectrophotographic photoreceptor according to claim 6, wherein m inGeneral Formula (I′) is an integer of from 4 to
 6. 8. Theelectrophotographic photoreceptor according to claim 1, wherein theuppermost surface layer is a layer including a film that is formed bypolymerizing or curing the composition containing the charge transportmaterial (A2) by using heat, light, or electron beams.
 9. A processcartridge comprising at least the electrophotographic photoreceptoraccording to claim 1, and being detachable from an image formingapparatus.
 10. An image forming apparatus comprising: theelectrophotographic photoreceptor according to claim 1; a chargingdevice that charges the electrophotographic photoreceptor; a latentimage forming device that forms an electrostatic latent image on thesurface of the charged electrophotographic photoreceptor; a developingdevice that develops the electrostatic latent image formed on thesurface of the electrophotographic photoreceptor by using a developerincluding a toner to form a toner image; and a transfer device thattransfers the toner image formed on the surface of theelectrophotographic photoreceptor to a recording medium.
 11. A method ofproducing the electrophotographic photoreceptor according to claim 1comprising: forming a coating film by coating a surface to be coatedwith a coating liquid including the composition that contains the one ormore charge transport materials (A2) represented by General Formula(I′); and forming an uppermost surface layer through polymerizing orcuring of the coating film by heating the coating film in a condition offrom 100° C. to 170° C.